Warning: this is a bit of a rant.
I've been on these forums a couple of years now, and I've played plenty of SWRPG as both GM and player. Most people who have spoken to me will know that I'm pretty positive most of the time, so this is somewhat out of character, but I really I find that I'm getting frustrated with this system.
The core mechanic is fine. More than that, actually - it's awesome . It's the reason I've played this system as much as I have. And it is particularly good in combat, where the use of Advantage and Threat can have very clear effects that are, even across multiple splat books, pretty well balanced. 1 Advantage ≈ 1 Strain ≈ 1 Boost die (unspecified). 2 Advantage ≈ 1 manoeuver ≈ 1 Boost die (specified), and so on. Combat is actually really solid, for all that it's abstract. The Slicing Encounter rules from Special Modifications are also actually really good, and there's a few other examples.
But beyond that, the actual application of the rules is either extremely vague (healing, squads/squadrons, what counts as an encounter, etc.) or downright confusing (defence being probably the most-discussed example on these forums). Some of the other subsystems seem great, but are often remarkably sparse: I know, for example, there are plenty of people here who like the Chase rules, but seriously? There's a chase scene in every single Star Wars movie, and just one page of rules for running chases compared to a whole chapter on combat?
And the relative value of Advantage/Threat/Triumph/Despair is mind-bogglingly inconsistent - a Triumph can upgrade your next check (providing a fairly meagre 4-5% increase in Success odds, although admittedly that doesn't account for the increased chance of Advantage/Triumph), or, according to the rules, provide an NPC who is predisposed to help the PCs (Charm, Negotiation), or inflict strain equal to the damage of the attack (Boarding Actions, Forged in Battle ). Things are even more lopsided with Despair, which can range from "upgraded enemy check" (a single turn effect) to "minor damage to a weapon" (adding a setback for at least the entire encounter) or "out of ammo" (kind of pointless since every PC now just carries extra reloads) to "suffer critical injury" or even "you are now lost in space".
Don't get me started on the fact that, mathematically speaking, a Boost die is generally better than an upgrade. That's just poor design.
Not too long ago, I came across a review of this system over on the Alexandrian website. It was not complementary, and the author pointed out that everyone he's ever met who has told him they like this system has admitted they have severely modified the system. I left a comment disagreeing with his analysis, but recently I introduced a new player to my game and, in explaining the rules, I realised how many house-rules I actually run in order to make the game flow, and how many hundreds of hours I have put into reinventing parts of the game.
Why this is, I don't know. I feel like maybe FFG were so focused on being "narrative" and trying to prevent too much number-crunching at the table (which are good goals) that they kind of forgot to a) balance a lot of the game and b) be specific about the rest of it.
Of course, maybe this is just me. Maybe nobody else has found this, and I'm just being pedantic and rules-lawyery and whatever. But it is really starting to bug me, and that annoys me because I want to keep playing my games, I do enjoy it when it does work, and I love the heart of the mechanics.
Not entirely sure what I'm hoping to gain by posting this here...just seemed like something I wanted to share. Anyway, thanks for reading if you've read this far.
(NB: I'm sure there are plenty of people who are going to throw words like "narrative" at me and tell me that the mechanics don't matter, or something. I'd just like to pre-emptively disagree. I run extremely narrative games, with a great deal of input from my players. If the mechanics didn't matter, I'd just sit with them and make up Star Wars stories - the mechanics are what turn it into a game.)
TL;DR - Love lots about this system: core mechanic, obligation, combat, character creation, Force powers, and many other things are great. But I am becoming really frustrated with the extent to which I have to house-rule in order to make the game work.