i expect the demoman will get some sort of high explosive he throws in a high arc, probably a stick of dynamite but maybe nitroglycerin or something
spy will almost definately get some sort of pistol: definately weaker but the gun bullets would be extremely hard to see and it'd be slienced: maybe a silenced glock or something?
the scout will almost definately get some sort of weird wooden bat: maybe a really much larger actually two handed bat that he uses it to knock people away from him, to get him with some sort of different scattergun, or even better an SMG
engineer might get a hammer rather than a wrench: useless for building his sentries, he'd have to let some other engineer to upgrade his sentries, but good for knocking out opposing sentries: maybe he would throw them at a good rate?