It's a bit tedious as it is, once you hit 200+ turns the game takes a while to process a turn and there's lots to do per turn, so cleaning up 50 odd enemies in a cluster is really tedious and basically revolves around having a tonne of ships in an area swarm the enemy, and even with modded mass / faster ships it's a chore because they can only do one kill per turn (2 if you include the missile). But it wouldn't be a chore if you gained XP properly,  I'm constantly upgrading survey ships but i haven't upgraded a single warrior ship yet. Maybe increase the XP for kills to make whackamole feel like more of an experience and for later game when you come across absolutely insane numbers of flying dragon ships perhaps a multi-action upgrade that costs 10 Antimatter or something huge, and maybe no max number of those, so you could have a 5 ship alpha cleanup crew go trash the baddies.  I think resource costs are a good place to contain your game throttling rather than spreading it thin, it gives a side goal, to secure more of a particular resource.