I could talk all day about how I would fly on a ship with a SAC member as captain, any day of the week. I started idolizing Cactus, Lambert, and Tropo's piloting skills since my early days of GoIO (main reason why I was personally invested in trying to join their ranks).
However, I'll leave that biased opinion out of this list:
Spud Nick scares the balls off of me. Seriously. Unless I have a lobby of skilled players on my team, I rarely stick around X_X
Jub Jub is one of my favorite pilots to try to test my skills against (I usually lose, though lol)
actually, a handful of pilots from SPQR really make me feel like I'm back in my Novice days. Very humbling learning experiences.
LeMoon is very high up there on my list of pilots that I always flock to be on their ship. Always a fun pilot.
Mr. Trickery is always a delightful pilot to fly under.
Rucin is new to the game, and is on my list because they are doing an excellent job of learning the ropes. Really putting in an effort to support gun-arcs and stay away from Galleon broadsides xD
Same goes to FreedomSoul.
I will leave a lot of matches or ships if the captain seems extremely uneducated on game mechanics, but I'll jump on those two Pilot's ships in a heartbeat.
I love new pilots that show potential. It's like watching the next generation of 45's that get tossed on this list, while they are still growing and learning and getting better. Almost like reading a really good book, and watching the plot start to unfold and take shape... That's a learning experience for me, all on it's own. Very magnificent, in my opinion.
EDIT: Derpy Squid is my favorite co-pilot for casual gameplay. He's very inexperienced with it, and has this sort of, timid piloting style. It literally brings out the best in me. My brain registers the match as "if I don't carry, and IDDQD myself into godmode, we will lose." He isn't terribad or anything, but something just clicks, and I suddenly learn how to pilot, and we do an amazing job staying together and bringing the pain.
One of my personal favorites to fly under, as well. Calm, perceptive, and eager to fly moar good.