OK, I'll go right out and say what I had in mind. I'll copy this over in the new nominations poll once it gets posted.
Mobile Repair Stations: Too knowledge expensive for their limitations, especially when fortresses and engineers can be unlocked for similar K costs but have much more to offer. See the various mantis posts I made on them for suggestions about how to make them worthwhile:
6064: Reduce MRS Repair Cooldown after move,
6066: Increase MRS Self Heal Rate Also, reducing K cost to 3000 seems reasonable.
Neinzul Enclave Starships: Their self construction rate is pathetically low for something that is supposed to work "on the field", which implies that engineers are frequently not readily available. I would suggest increasing base self construction rate, and having the self construction rate go up with Mk, giving a reason to unlock higher marks beyond just less Mk. limitations. They could also use a buff to health, but that is not as important
Etherjet tractors: Their health is PATHETIC, even by fragile ship standards and their higher than average ship cap. They should remain on the fragile side of fleet ships, because of how much pain they can cause when used correctly, but right now its a bit too fragile. The low attack is fine though.
Bomber starships: Their DPS is fine; its pretty good even by starship standards. My main problem is their health. For a close range unit, they don't seem all that terribly durable. Even the Plasma Siege Starship has more HP than these (though, admittedly, bomber starships have armor). A health buff or possibly a large radar dampening range. (Remember, larger radar dampening means less effective radar dampening).
Slight (like, 1.5 slight) hull multipliers similar to the bomber fleet ship may be nice for thematic reasons. I'm fine with their "large stuff only" restriction.
EDIT:
Spirecraft Sheild Bearers: What to do about these has been endlessly debated. However, can we at least get a HP buff so that they are comprible to normal forcefields? (See
5565: Spirecraft Shield Bearer HP)