I grew up fascinated by the Battle of Britan and the ensuing European air war so when I signed up for AW 17 years ago my first choice was the Spit IX which I flew religiously (My brother was at my house one day and I actually got him to try playing. We were in a Pacific arena and he chose the Hellcat. More on that later) so I came to AH and stuck with the Spit IX.
When the Spit lineup was expanded the 2x20mm, 2x.50 cal package was eliminated from the IX but reappeared on the XVI. I didn't like the .303's so switched to the XVI.
Along the way I've flown the entire planeset to at least a 2:1 K/D ratio in one camp on a few occasions in order to learn every plane at least rudimentally.
So where am I today? Here's my top flown planes (roughly in order) although now I play so little it might take months to get to the lower on the list:
Spit IX (Fighter)
FW190A-8 (Fighter/Buff Hunter)
F6F-5 (I told you we'd get back to it... Fighter/Attack)
Bf109K-4 (Fighter)
Lancaster (Bomber)
Honorable mention (other planes I like to fly on occasion):
A6M2, AR234, Bf-110G-2, Boston, D3A-1, F4F-4/FM2, Ju-87, Ki-61, Me-163, P-38G, Spit V, Spit XVI