How about...
A couple of sliding targets (bit like the one that was on a rope a while ago), that slide into and out of view. Once chance at it. Put a no-shoot inbetween. Shot through a window.
A rabit hutch covered in black, so you can't see the target - have to aim without site picture unless you go prone. Put a puddle in front of it to stop going prone. Use mini targets
A speed stage, with say 10 targets set out a bit like a steel match, compulsory mag change. Two if you want. Finish on a long distance popper.
Could vary it by forcing targets to be shot in sequence, on either side of the range - left right left right left...
Mike.