Ok, sounds nice (<-- BIG understatement)
I found this website which mentions Me-410s with at least 4 20mms (search for B-2/U-3/R-5):
Here Anyway, I think it would be nice to have the B-29, for the reasons MajIssue gave, and the Me-410 (with an option for as many 20mms as it ever carried), both with extremely heavy perks.
Here's my logic: the Me-410 could join the 262s and 163s as being only spawnable from bases right near HQs (maybe the same for B-29s), so then people with loads of bomber perks could up several B-29s on an HQ mission, shoot it out with the Me 262s, 163s & 410s, and then see what happens. Neither of these planes would probably unbalance things
too much, as they'd only be spawned from bases near HQs (aside from the 262), and they'd have huge perk prices anyway.
Yossarian