I'd have to go with the T-70. It's pretty balanced. Has okay offensive output and defensive abilities, pretty decent self sufficiency for a small based ship. One top tier pilot, and a few casual pilots that are more than viable. Generics are fun as well. A good Poe player is frustrating to fly against, a bad Poe player can still do some damage and be annoying enough. Jess Pava is always a strong ship, Nein Numb is fun for control, Ello Atsy is hilarious with flight assist, Snap can be super slippery.
Tie S/F is a strong contender too. It's very effective if flown properly, it's not invulnerable. Both pilots can cause some damage. Overall pretty fun ship to fly. I need a second one...
Tie Defenders should be in this too.