What if Exp was only gained by killing AIP-generating structures (and Instigator bases)?
I like that idea quite a bit.
Possibly we could also make it so that other things generate EXP if they are not something that is renewable. That would encourage SOME farming by players (of raid engines themselves or something like that), but I think that's a neat way for players to go about getting EXP.
The only question, then, is how defensive stuff gets EXP. The most obvious thing is "every time it survives a wave," but I'm not really sure how to define that. A wave arrives, and that's a distinct event. The wave being thwarted... that's less of a thing. Does it count it when the wave is no longer on the planet? What if it just ran off to the threatfleet? Shouldn't surviving a big incursion from threatfleet also count? Defending against a CPA, etc?
We also get into some strange situations where, even on offense, you can then choose who does the killing blow to the few AIP-generating (EXP-granting) structures, and which ones you micro off of the planet. The one benefit of the EXP coming from the smaller ships and all the minor stuff is that it's something that is... well, constant. If you use three offensive fleets as part of the main offensive against a planet, but then withdraw them at the end, you've still split the bulk of the EXP from them.
So basically anything to do with trying to have EXP penalties for fleetballing is going to be super duper easy to game in a way I'm not thrilled with.
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Okay, so rethinking once again, maybe the current EXP setup isn't that bad.
To some extent, perhaps EXP should just be on things that are non-renewable...ish: floods of AI ships as the solution to so many thing that you're having to defend against are dicey, anyway; maybe having fewer ships that are spawned from those sources, and having those be explicitly zero-EXP-granting might be good.
Aka, perhaps the things that a Raid Engine spawns are explicitly of a sub-variant type of usual ships, and they are both stronger than usual (like our Dagger variants and whatnot), and also grant zero EXP. Same thing with the ships that are spawning out of a superterminal and other things like that. Then we can use fewer of those ships, but make them extra scary in some way (extra fast from raid engines maybe, extra tanky from the superterminal maybe, etc).
With us being able to directly define EXP on unit types, all the exceptions aren't really going to be that hard. You just don't get any EXP from dyson stuff, for example, and the tooltip would clearly show EXP granted of 0. And for the things that are conditional (like certain kinds of waves), it's not something that we make some sort of strange exception to ALL ships, but they just generate new sub-variant ships with 0 EXP and some extra powers, which is easy enough for us to generate in xml and actually is pretty interesting anyhow (having unique ship variants coming out of those things that generate infinite ships based on your actions strikes me as interesting in and of itself, EXP aside).
The impetus for players to go and just farm planets for EXP is something that is unfortunate and I'm not sure what to do about that, but at least the impetus to fleetball would be gone, so there is that.
And perhaps we could make some sort of small AIP cost for every guard post that is aggro'd? Like 0.1 AIP or something? That way just going blitzing through planets and not using your transports and efficiently avoiding things is going to cost you some AIP (enough to give you pause) anyhow.
If the game has been too easy, then another source of AIP for the AI, and one that is harder to avoid but also very small, might be good in general. Another player was talking about the need for passive over-time AIP increases for AIs to return in order to give some sense of time pressure in a good way (aka not having infinite time to just refleet and whatnot, even if the over-time AIP increases are small), and that is another thing that inherently would disincentivize stopping to farm the roses all the time. And which would help even out the game's difficulty if it's becoming too easy (the over-easiness of EXP granting aside, right now).