I like the Me309, and have always thought the design was given short shrift from applied apathy on the collective part by Messerschmit and its designer(had to have been a committee). But that never stopped certain kit manufacturers, as well as the modellers who love them.
I have a pair of Czech Master 309s, but never got around to doing anything with them, which may be changing soon.
A twin engine Me309, however the engines will not be mounted on the wings. I realize that that's a fairly simple mod, takes another kit to supply the needed parts, and more than a few modellers, as well as a few aircraft manufacturers have done so, usually with an additional fuselage.
But what about a push-pull design? The Do335 would have done quite nicely, had it been able to be deployed in squadron strength. And a 1/48 Do335 kit does have a pusher prop.
Not sure if I'll stay with the wings in a 309 kit, because prev erring a bit of plausibility, another engine does add a bit more weight, which would stress the wings and render it a bit squirrelly, so, a constant chord center section that also supports the pair of tail booms, as well as the empennage, as well as the stab spanning the width of the booms.