Whenever I build a fleet containing an ISD 2 it has always the same four upgrades (plus varying titles and/or officers): Gunnery Team, ECM, XI7 and Leading Shots. That is...boring. Are there other competitivly usefull outfits for those four upgrade slots of an ISD2?

I feel your pain. It's my default go to. However, could try the palsy ISD, Avenger, overload pulse, XX-9, and ECM, gotta double arc a lot though, or bring spendy raider 2s with op.

Another fun one is a squad controller, relentless, flight controllers, EHB, and ECM, bring howlrunner with ties or interceptors

Not really.

ECMs is for fighting big ships with big hits, where you absolutely need that brace. Advanced Projectors is better against bombirs and small ships. Might be a place where you can shake it up depending on your local scene.

Don't need Leading Shots if you have Darth Vader as your admiral.

XI7s are good, but against are less useful against small ships.

Darth Vader (or Veteran Gunners)

Spinal Armaments

Reroll 5 red (+1 for CF) at long range! Swat a Flotilla out of the sky before it can get close. Cripple TRC90s. Match Ackbar AF2s shot for shot.

Heavy Turbolaser Turrets

SW7 Ions

Seriously, unless you are expecting CR90s and MC30s and nothing else, this is just hetter than XI7 for hunting the big ships. And your 140+ point monstrosity should be hunting the big ships.

ECM is a necessity though, unless you are being cute with Advanced Projectors.

I find that XI7 is excellent against small ships.

It allows you to kill the ship even if you didn't roll a large amount of damage.

You forgot Intel Officer and Quad Lasers in this age of many bombers.

And sorry but Intel/Xi7 is better in almost all cases that matter. You can almost always count on the one accuracy which means anything without ECMs is having a very bad day. Anything with ECM - that's why you have the intel guy.

Intel Officer, Leading Shots, XI7, ECM, Gunnery Team

...these really just seem like the best ISD upgrades when you don't know what you are going to be facing. It's a solid "all comers" build.

I'm trying out QTC and Sensor Team. Leading shots is just too good not to take, but consider Overload Pulse with Screed. This build makes for a great sniping ship, effective against small and medium ships while at long range. Once you get to medium, you can really put the pain on large ships, and with fighter support/focus firing, you can bring things down fairly quick.

You can replace Gunnery Team with Sensor Team for extra accuracy.

Sometimes I ditch Leading Shots for MS-1 to target their ECM with the side arc first shot so they can't use it against your front arc shot.

Needa / TRCs is a fun combo. Swap a redirect for an evade, and use that evade to guarantee a double hit. Works particularly nicely with Tagge, and you can team it up really nicely with Devastator. Evade a shot in turn two, burn the evade for the red double hit on your first attack, get an extra blue for the second attack, and by the time turn three rolls around you get the evade back.

What you are describing I would call the battleship loadout. My other standard loadout is actually for an Imperial-1 fitting as a fighting carrier, with Flight Controllers, EHB, Boosted Comms, and Turbolasers and Ion to taste. If I want to fend off slicers I'll add officers as desired, or use Wulff to dial up that squadron command even further with an immortal token. Six of any Imperial squadron can go to town on quite a few things.

Same as I do with a Liberty.....

Ion Cannon Batteries, XI7s, Fire Control.

I am going to punch your Hull Zone... HARD. So Hard you'll feel it in the Squadron Phase. With a face up.

Of course, the Liberty punches even harder by adding XX9s to the Mix.

Depends on the role.

Ion Cannon batteries can be an interesting upgrade, especially against Yavaris.

Spinal Armament is a solid upgrade for ISD2

In the current age of squadrons Cluster Bombs may be worth looking at (but it'll require a right build and a right meta)

Tractor Beams is a solid upgrade to counter Craken

Such a tough question because the ISD has so many different roles. Carrier, Tank, all rounder etc..

I personally think people put far to many upgrades on them and they become expensive liabilities. I don't run many big squadron fleets so I often use either just an ISD 1 or 2 with minimal upgrades and it really isn't the main source of damage. I leave that to a flanking Demo. The ISD is to draw attention and be the anvil that you can't ignore coming at you. ISD1 with just Intel and ordinance experts is solid if you are running Screed. With the new fighter heavy flotilla meta I've experimented with just an ISD2, Gunnery team and skilled first officer. You need to be able to shoot at both squads in your front arc and a capital ship or flotillas. With Screed you can turn 2 blanks into at least 1 crit but you are still vulnerable to a really terrible bad luck roll but it doesn't happen often. This can also work if you run an ISD and a heavy Rhymerball. If you have initiative and another heavy damage dealer I find you often don't need ECM's as you can control the engagement and get in your damage before he ISD goes boom. Then since you didn't make it a glowing Christmas tree with upgrades even if it does blow up you can still recover and get a good sized win.

Needa / TRCs is a fun combo. Swap a redirect for an evade, and use that evade to guarantee a double hit. Works particularly nicely with Tagge, and you can team it up really nicely with Devastator. Evade a shot in turn two, burn the evade for the red double hit on your first attack, get an extra blue for the second attack, and by the time turn three rolls around you get the evade back.

Better plan:

Double hit on the first attack. Double hit on the second attack, and what's this? I have a discarded defense token! Add a blue.

Needa / TRCs is a fun combo. Swap a redirect for an evade, and use that evade to guarantee a double hit. Works particularly nicely with Tagge, and you can team it up really nicely with Devastator. Evade a shot in turn two, burn the evade for the red double hit on your first attack, get an extra blue for the second attack, and by the time turn three rolls around you get the evade back.

Better plan:

Double hit on the first attack. Double hit on the second attack, and what's this? I have a discarded defense token! Add a blue.

Except you've already attacked twice and will lose the blue at the start of the next round when you recover the lost evade. Much better to avoid some damage, take a guaranteed double on your first shot, then add a blue at long range that you can leading shots with.

Needa / TRCs is a fun combo. Swap a redirect for an evade, and use that evade to guarantee a double hit. Works particularly nicely with Tagge, and you can team it up really nicely with Devastator. Evade a shot in turn two, burn the evade for the red double hit on your first attack, get an extra blue for the second attack, and by the time turn three rolls around you get the evade back.

Better plan:

Double hit on the first attack. Double hit on the second attack, and what's this? I have a discarded defense token! Add a blue.

Except you've already attacked twice and will lose the blue at the start of the next round when you recover the lost evade. Much better to avoid some damage, take a guaranteed double on your first shot, then add a blue at long range that you can leading shots with.

Then that round you:

Double hit on the first attack. Double hit on the second attack, and what's this? I have a discarded defense token! Add a blue.

Thank you all for your advise. Especially the reroll alternatives I consider quite intriguing. So you can swap the Ion Cannon slot slot for High Capacity Ion Turbines, by which your side arcs become stronger which let you ditch the Gunnery Team for other niceties. Great. I will try some of your suggestions.