You're missing the point Oleg...
By using bomber perks to buy a perked fighter, you're at least giving the player the perception that he's got an advantage over everyone else at that time. It comes with a risk, of losing the plane and the perks, and truth be told, a Tempest in the hands of an inexperienced fighter pilot isn't really that much of a threat, is it? Just makes for a slightly faster target to kill.
I've gotten real good at hi-alt bombing...but those perks end up sitting because my only perk option is an Ar-234 with three bombs...big whup.
If you're good at all aspects of this game, this is a moot point. But not everyone is.
J