No consideration as far as usage, perks, usability in the MA whatever is concerned. I just like to dream like anyone else.
Boulton Paul Defiant : Would be useless, terribly underperforming and whatnot. But the idea is so appealing, why fix guns on a a fighter, just slap on a big bulbous turret with 4 peashooters that can fire the 'ole Messerschmitts in the face!
A Messerschmitt Bf-109 T2 : Some were built, they were delivered but never flew from carriers because the Germans never finished theirs. Just tweak our E-4 and enable it from carriers. Impact on the game near zero but would be fun. When we're at it, enable the Stuka too.
A low altitude Spit IX or maybe a XII (slightly perked) : Enough Spitdweebs as it is but I think it would fill a gap in the planeset.
Talking about gaps : What about the huge numbers of Yaks? -1 -7B, variants of the 9? I do not know much about them but we don't have early war Russian stuff. Model the I-16 too because it is significant and soooo cute.
Ki-84, Ki43, P-39, simply no excuse to leave them out.