I like the idea of steam-age technology, although I would guess it have elements of Jonas tech, like cupronickel components with strange glowing lights/liquids.
Firearms would be a fitting addition, as evidenced by the popularity of the mod.
I'm really hoping for a rail system ala the other block game, it doesn't have to be generic minecarts, how about temporal gear powered carriages?
We did get a moving elevator chair in the Devastation.