Think bigger.
Have a shield module, which stacks on more shield HP, and a shield RANGE module, which stacks on more range (and maybe a little extra HP, to make it worth the slot). Then have a shield regen rate module too, and maybe a shield power drain effeciency module (probably max 1 with maybe some side stats).
Any one of these modules would give you a basic, short ranged shield focused more towards it's main stat, further ones would stack up.
The max modules can be 8, or 5, or 2, or whatever. The decision here is how large a maximum number you want, and what proportion of that you think is 'worth' a module slot. Say you might want only slightly more than a regular shield generator in range at max, but is 100 shield range worth a module? Maybe 200 is, so if your max range is 600, that means you want 3 range modules max. That's always how you should design module counts, the 8 module thing was always arbitrary.
Bonus points: Have the shield HP module sublty increase the opacity with each stack so you can see the effect.
Conversion modules have always been a stupid idea. You should be able to work incrementally towards them using tradeoffs.
The same thing should be done with everything: Slow or EMP damage, accuracy and spread, weapon velocity, Rate of fire, beamtime on lasers so you can slowly convert your laser into a HLT then a Anni just by adding stats, burst rate so you can have a triple d-gun with 3x the reload time or an EMG that fires in rapid bursts or higher alpha on your riot cannon.
Hell, you want more regen options? There is a toggle in the game that allows a unit to repair itself with it's nanolathe. Support+nano or res coms would naturally pick this over autorepair if they want survival: With the tradeoff that they can't fire, move or build while repairing themselves.
Why not different regen modules too? Idle modules AND combat repair: Or modules that increase or decrease the idle time for a tradeoff. Vampiric ammo, for offensive based comms.
And hey, more defensive options than HP. Armour states. One kind of armour turns on when stationary (Crabe armour), another kind of armour turns on when not firing (Halberd Armour). These can stack too, say at 25% increased effective HP each module (Google might hate violating the purity of armour consistency for that though). Hell why not let players stack both if they have nothing else on their comm, so they'd be an invulnerable ball with 500% effective HP if they sit still and don't fire.
Make drones stacking modules, one drone per module, and add more kinds: Repair drones, AA drones, EMP drones, kamikaze drones.
I have a lot of these stuff already half implimented in local copies of Zero-K, but commanders are fairly owled so it's not so much worth the effort. Maybe one day I'll embark on this, but there is a paranoia that this will make comms more powerful, which I don't want to do, they're at an OK power point. Either way it would throw balance slightly into flux and so there would be lots of arguing and negotiating to even attempt something like this, since it's currently in a stable and safe state and non-balance-critical (on purpose).
Editing the modules modside is actually really very easy. Any one of you can do it if you want to see this sort of stuff happen and put in the man hours.
