@Alex: I was pretty surprised that this made as much of a difference as it did. The way I ended up doing it was very simple, too.
Other stuff that might bear fruit (but I can't say for sure from over here):
1. Storage of AI state-machine stuff and abstraction of the Fleet mechanics inside Systems. Probably can save considerable memory there.
2. Storage of inventories at Stations is probably contributing somewhat at large scales; memory growth from inventories is a slow creeping thing but basically, Stations are really big fleets and I suspect that the same issues that cause fleets to eat a lot of RAM are prevalent there as well.
I might do an experiment with that, in terms of just randomizing inventories when players visit a Station; that has positives and negatives, though. IDK how that data's being handled, I always assumed it was just longint (type of cargo) longint (stack size) in an array per Station, since that's the most memory-saving way to do it, most likely.
3. There's probably some overhead in OrbitalStations that will get worse as state data gets stored there (things like mission states, etc., looking towards the future).
@Annex:
1. On the Universal mounts, I'd like more detailed feedback. Given what's happening with missiles in the next build, where they're more deadly (and considerably more CPU efficient), I'd need more specifics before I'd want to change it. Besides which, there are several "missile boats" in the Capital class- the Macuahuitl in particular is really quite nice for that role.
2. The Cruisers are meant to be pretty specialized (see the Wall of Text). There are non-specialized Cruisers that can do a lot of things, such as the Eagle, but they're generally meant to file niche roles and round out the uber-fleets.
On the other hand, certain things are coming in the next build that will make it possible to re-task certain Cruiser designs that are kind of out-classed in late-game play. The biggest single change is that there's a new Hull Mod, Bubble Shield, that offers a 360 shield to any ship. The shield's low efficiency means it's not a perfect solution, but for problems like how to keep late-game Dominators relevant, it's pretty nifty.
3. I, er, killed a Pergon with a Chiron (that's a weenie little Frigate) today. Are you saying that Exigency's just too OP in player hands (which wouldn't surprise me, at least not the Pergon), or are we talking about having trouble killing them as a player?