actually mine would be very simple,
it would be a 262 complete and as is from the end of the fuselage forward
mated with the very tail end, including rocket of the 163.
use the 163 rockets to get you up to the stratosphere in seconds, and the 262 engines so you can stay up there all day.
course it wouldn't break my heart if you could remove 2 of the 30mm mk 108's (80 rounds) and replace them with 2 40mm vickers with as much ammo as you could shove inside.
make the 30's and 40's able to fire separately! no sense in chucking 40's at a pony!
if it is allowed by the rules i would sweep the wings back. i would keep the size similar to the traditional 262, but would sweep them back in a manner similar to the 163.
no bomber would ever know another moment of peace or serenity above 10,000 feet again.
both bomber crews and high flying escorts would tremble at the whisper of the name of this evil boy when he comes to town.
sorry i couldn't explain everything as well as you did RAM but i gave you what i could.
FLOTSOM