1. I think that, when it comes to ships that really only work well under specific circumstances for the player, those should be out of the main fleet design lists. Knowing what those are, and making hand-designed fleet types that show up more rarely would be good. Aka having Raiders always be in an all-raiders fleet when showing up for the player, or space planes or whatever being in a combo with something else that's good just with them, should help.
That'd help with Fleets that have counter-active unit types (like Raiders and Tesla Corvettes), but doesn't completely fix it, since there's still some randomly designed fleets. It was a nice idea in hindsight but...the tactics side of the game just hasn't stepped up to that well - can't really find uses for many units beyond "toss it blindly at something". Raiders being tied to a Fleet is still a problem for them. If the centerpiece is slower, then they have to wait for it and thus defeats the point of Raiders, or if it's faster (somehow), then the Raiders speed is also pointless since they'd rather hang about inside the centerpiece instead. Either way, they're affected badly by being part of a Fleet.
EDIT: Thought I should say that I still kinda like the idea of the random Fleets (I did support it internally). I think it was just let down by some other parts, not that it itself is bad. Some units...might just need changes to really fit this whole thing. Raiders are just a particularly good example.
2. Disallowing super-duper-expensive things from being part of the regular fleets might have some merit, I dunno. The point is, there's a lot of flexibility with the fleet design stuff versus it just being "eh, it could be any old combo at all," specifically to deal with some of the more edge-casey units. But if we're running into more cases of these than I expected so far, then that just means we need to adjust some xml.
This feels a bit worrying. If we start making it all specific combinations then it's kinda...not really much to do in terms of trying to find uses for a fleet. It'd be kinda apparent? But on the other hand you can't combine things like Raiders and Eyebots in any useful way in the current system either.
3. I do think that potentially lowering the difference between the mark levels would be good, so that things are not quite such huge jumps. That would then mean we need to definitely make the AI homeworlds mark 7, and their planets in general scale higher on average throughout the galaxy. It's way easier to get higher-level units now, compared to the first game (and with the XP stuff that will only be even more true), so the AI going up in power to compensate makes sense to me, while downing the difference between all the power levels in general. If mark 1 stuff is truly useless, well, that's just not good no matter how you cut it.
What were the reasons for Mark 6 and 7 originally? I don't recall seeing it, and it's always felt weird being able to out-tech an AI Homeworld en masse. Also weird that, because we don't have higher Marks locked behind Fabricators and Advanced Factories/Constructors, and no Design hacks left, that...there are almost no hack options that actually work on the AI. I think there's Science Extraction and...Super Terminal? The Dyson Sphere alone has twice that.
I wonder if not keeping the outdated ships when you increase their Mark level has caused this? With that you always had a sizable bunch, and they could still get something done. Or at least, give the impression of doing something beyond being the first to die.
5. Overall, when it comes to having some sort of sub-group that makes sense and is good for doing X task, that's really the entire role fleets are supposed to fill in the first place. Sometimes it's supposed to be "here's an interesting combo," or just a smallish battle group of stuff in general. But... maybe for the problematic units like autobombs, those need to only ever exist in fleets with just themselves, so they can be managed a certain way. Maybe... in some ways, maybe all of the strikecraft-based fleets need to be that way? That would be kinda gross, though.
Yea, as said above that kinda starts to go towards being fairly straight forward and kinda boring. At that point Fleets are kinda just...bigger power spikes in less planets compared to Classic, and unit organisation. If there are Fleets entirely of AutoBombs or Raiders or whatever, then it's...I dunno, like capturing an ARS, but the unit has a centerpiece it has to follow.
One thing of Fleets that's came up is...regarding things like the Fleet Concentration AIP, or whatever "carrot" approach is possibly taken, Fleets make it a bit clumsy to do unit combinations unless said units are in the same Fleet. Spiders and Agravic Pods can kinda work together (Spiders slow down poor engine stuff, Agravics shoot up whatever is resistant), but if they're in different Fleets then you have to bring both together to do that. If there's incentive to spread them out then...you're really at the mercy of RNG if such interactions are possible. This'd extend to AI planets too. If this thing has a ton of Concussion units, then ideally I'd want to keep units weak away, and bring in units resistant, but if I happen to have only one type in each Fleet, then I have to bring them together...thus, I have fleetballed. Just, more a ball made of several smaller balls.
EDIT: Though maybe the above point isn't that bad. Sometimes Fleets just need to come together for a while, and that's alright.
"Clumsy" is a word I'd use to describe Fleets after using them for a while. The organisation is nice, being able to move groups of units that reinforce cleanly about is wonderful, and something I would've appreciated in Classic, but the things like being tied to the Centerpiece causes a lot of issues, like Raiders and AutoBombs being ruined by it, and the above mentioned awkward scenarios of trying to do combinations. Not impossible to change.
Regarding units...I might make a separate topic on that. There was a complaint in Discord while we were doing the original Fleet update about everything dying too fast, it all seems like generic hammer compared to scalpel, etc. Might be something in that...hard to notice things like MLRS doing more damage to stragglers if everything dies instantly anyway.