A few ideas:
- FD scale jet airliner, either a first generation (e.g. Comet, 707, DC-8) or a contemporary one.
- FD or Shipbucket scale launch vehicle/launcher family. Could be constrained to e.g. the first manned launcher of a country or a Moon rocket if this is too broad.
- FD scale manned spacecraft. Could be combined with the above, i.e. two views, one of the spacecraft itself and one on top of the rocket with fairing and/or a launch escape system.
- Shipbucket scale merchant ship challenge, or one converted to a merchant cruiser/raider/hospital ship if people prefer doing military stuff.
- Shipbucket scale paddle steamer challenge, could be constrained to e.g. tugboats or coastal passenger ships if it's too broad.
- Shipbucket scale yacht challenge, either a motor yacht or a sailing one (or both).
- FD scale locomotive challenge, or even a complete passenger train. Could also be constrained to e.g. high speed trains or steam locomotives.
- FD scale car/bus/lorry/etc challenge. Maybe an 'anything goes as long as it's road legal'-challenge.
Basically, I'd like a non-military challenge, just to change things up. All those greens, browns and greys get a bit boring after a while.