I tackled a big ship. It was a battlesh cruiser, full of plasma-armed soldiers and a provost! Nevertheless, it wasn't particularly successful assault: I lost 11 gals and 2 power armors.
Aggressive tactics worked really well for a first few turns: I killed a lot of them without losses (aside from 1 gal, who got MC-ed on first turn and killed another gal) and even stunned an esper! Then a stray grenade killed her, and it went downhill from there. My overstretched forces couldn't survive the counterattack, and in the end, only five gals remained, two of them unconscious, and one in the vanilla coveralls (also known as NONE armor). To add insult in injury, last enemy threw a grenade into cargo tile of Bonaventura, mind probe gal survived, but some equipment was destroyed.
After that, I caught lesser ship and got two espers, one for research and one for interrogation, so aside from $2+m gained, attacking the cruiser was pointless, and I was dumb.