Only thing I see is the matter of speed and upgrading by silhouette difference.

If Speed is 1 and the sil difference is 3, do you roll RR or RPP?

If you "upgrade" by the difference, it's RR. If your intention is for it to be RPP, you'll need to adjust the language. Maybe something like:

"When making the Piloting check, the difficulty is equal to the target's speed, or how many points of silhouette the target ship is smaller than the attacking ship, whichever is higher. The lower of the two values indicates how many times the difficulty of the check is upgraded."

3 hours ago, P-47 Thunderbolt said:

"When making the Piloting check, the difficulty is equal to the target's speed, or how many points of silhouette the target ship is smaller than the attacking ship, whichever is higher. The lower of the two values indicates how many times the difficulty of the check is upgraded."

Yeah, this is what I intended, I just couldn't find an elegant way of putting it, so I half-buttet it for simplicity. But you're absolutely right; highest score determins purple dice and the lowest one how many of these are upgraded to red.

I'll post an update here since several forum patrons found the earlier discussion useful.

We're now three sessions into the battle with probably two more sessions left to go, and MAN have I made some mistakes here! But it's all good; this is a learning experience, which is also why I started this thread in the first place

SOME OBSERVATIONS
-- Number of Phases : In my scripting of the battle (see above), I envisioned as many as 5 or even 6 phases to get through it all, this despite it being a rather small skirmish (120 troopers + 2 AT-ATs with starfighter support vs. c.80 troops + defense preparations with starfighter support). This, however, is proving to be way too much; My entire 2nd phase (2a Rebel Swift Retreat & 2b Rebel Fighting Retreat) could've been cut with no major narrative loss and about one zoom session saved. FFG's SWRPG is cluttered and complex (yet lovely) at the best of times, and I have certainly learned that the GM should seize any and all opportunities to de-clutter and speed up the Structured Time game play. In other words, whenever you're planing a Mass Battle, I advise you to condense it into as few phases as possible to keep it from dragging and loosing momentum. 3 or 4 phases should probably suffice, and if you can do it in 2 with a cool climax, then more power to you!
-- Individual PC events : Ok, here I made another mistake... The way I envisioned it was this large battle where each of the PC heroes got to do a private three-round encounter every phase, tackling a scripted/personalized problem, the outcome for which would influence the end-of-phase Mass Battle check. Cool, right? In theory, yes, but in practice, OH-MY-WHILLS! Even with only three rounds per PC, this system is taking for friggin' ever! I devised this partially out of necessity, to give the pilot an event suited them, and the same for the battle leader, etc. But I did not need to divide ALL PCs into separate missions, and it turns out that when they join forces and tag-team to troubleshoot a single problem, that makes everything MUCH faster. Strangely, two separate three-round combats take a lot longer to game than one dual-PC three-round combat, even though you make virtually the exact same number of dice rolls. Who'd a thunk? Again, here I advise that GMs do their best to script flavorful & personalized Battle Phase events for teams of PCs rather than individual mission as I did; if at all possible, make it so that ALL PC heroes partake in one single hoo-ha (although we all know that this is rarely practical - the pilot is going to pilot and the Jedi is going to Jedi, etc.).
-- Altered Squad Combat Rules : In my infinite wisdom, I decided to expand the Squad rules to give squads & squadrons more agency. In short, I give the controlling PC and the squad (and in one instance even a named-character sub-squad leader NPC) each a turn every round; same went for Imps, where Stormies, their Sergeants, and any Rival or Nemesis boss would all get a turn. (As written, the squad rules dictate that only the squad leader make a single combat checks for the entire group, with the squad offering a bonus of some sort, typically a situation specific Boost Die, and also function as a meat shield for the squad leader). In other words, I gave the active player the corresponding Adversary Card and made them roll checks for their minions as well as for their own PCs. This was another mistake on my part, as I defied the entire purpose of the Squad Rules, which is to condense combats into a single hero action per turn with minions offering narrative support, ending up instead with two or three Rebel checks and at least as many Imperial checks every combat round. In other words, rather than having a three-round mini-encounter where the PCs, supported by goons, make one combat check each turn, I ended up with a three-round mini-encounter with at least three combat check on either side.... Basically, triple the work and 1/3rd the fun. Lesson learned = don't mess with them rules. People like @KRKappel & al. knows their stuff

This has been a steep learning experience for me, but luckily the players -- despite the battle taking forever (probably around five sessions in all) -- are professing to having fun (phew!). With what I've put together for this campaign, we're looking at at least two other major Mass Battles (i.e. Friends Like These and Onslaught on Arda I ), plus possibly one or two more, and I'll definitely strive to simplify and speed things up the next time around.

I hope this has been interesting to follow for some of you, and if not... I'm sorry for wasting your time 😛

For the squad/ron rules, only change I'd make is allowing the squad to, as a whole, make a single combat check as part of the commander's turn, using standard minion rules.
So a squadron of 12 with an Agility of 3 rolls YYYGG.
This change simplifies things dramatically while allowing them to contribute.

As for having individual encounters for individual PCs, I definitely agree with you there. Aside from a separate combat for the pilot (because it kinda has to be, though you can easily wrap it into the same initiative order/sequence of events), I'd have suggested wrapping it all together if I'd realized what you were talking about.
The reason it takes longer is probably because the PCs can't feed off of each other and plan their turns on the other PCs' turns, meaning decision making takes longer and they have to do a lot more individual strategizing.

5 hours ago, angelman2 said:

-- Number of Phases : In my scripting of the battle (see above), I envisioned as many as 5 or even 6 phases to get through it all, this despite it being a rather small skirmish (120 troopers + 2 AT-ATs with starfighter support vs. c.80 troops + defense preparations with starfighter support). This, however, is proving to be way too much; My entire 2nd phase (2a Rebel Swift Retreat & 2b Rebel Fighting Retreat) could've been cut with no major narrative loss and about one zoom session saved. FFG's SWRPG is cluttered and complex (yet lovely) at the best of times, and I have certainly learned that the GM should seize any and all opportunities to de-clutter and speed up the Structured Time game play. In other words, whenever you're planing a Mass Battle, I advise you to condense it into as few phases as possible to keep it from dragging and loosing momentum. 3 or 4 phases should probably suffice, and if you can do it in 2 with a cool climax, then more power to you!

I haven't had the opportunity to run a mass combat so I'm not speaking from experience here, but I think it's more about how you use them and how significant they are. Mass combat checks can be resolved pretty quickly (I have tested that, though again not in-game). Your phase 2, for example, can easily be skipped.

Personally, I prefer having more steps as it gives more space for tactical adjustment and can help average out the results so a pair of hot rolls don't completely throw your story into disarray.

Some more observations (after talking the battle over with my players now that it is all over after... 4 game sessions).

Length : My players though 4 sessions were within the limits of reason and were pleased with the games. (Phew!) So, perhaps it was just me that thought 4 sessions to a battle was a bit much

Focused, 3-round PC contributions : This was something the players really appreciated, that instead of fighting out larger encounters, everything got distilled down to, "you've got three rounds to do your thing this phase, the result of which will influence the battle". They really liked the immediacy of this system, and it is something I think I'll try to use more in regular games as well; instead of rolling out 7 rounds of fighting the scumbags in the back alley, perhaps we'll go 3 round and decide the outcome of the encounter based on that -- to let the narrative drive the plot, but be informed by short bursts of dice action. This gives the GM greater control of the story, and makes it easier to do some themes and tropes that can otherwise be hard to pull off with a dice game, like... "you've ran out of ammo and the zombies are closing fast" (which would take forever to actually roll out).

A set end-point : I believe putting a narrative end-point to the battle was a smart thing (rather than keep battling till one side was defeated). In the current battle, the Imps were much stronger (at first) than the Rebels (5:2) yet not highly motivated, and the PCs had a chance to whittle the difference down from phase to phase, and once the two sides were of equal Force Strength, the Imps would grow weary of the entire thing and sue for a ceasefire (of course, there were narrative reasons why they would do so). This worked very well and spared us at least another session of Mass Battle, and everything ended on an interesting scene of negotiation. Cool stuff!

All in all, the Mass Battle -- like everything in this RPG system -- had a steep learning curve, but was fun and interesting enough to do. Everybody felt like their PCs contributed importantly to the battle, and it all turned into a rather memorable story arc. Now, only two more battles to go in this campaign, each one larger and more complex than the preceding one... Oh dear...