First, what structure exists on the ceiling to rig things to? Assuming you have appropriate structure:
You say "signs:" if they're small and rectangular (say 8' wide max) I think an oleo would be a good way to go.
You say "folliage:" not sure exactly what we're talking about, but if it's something with an organic shape that would be okay to "bunch up" (and is lightweight) you could rig it as a modified Austrian drape, with series of D-rings stiched up the back with lines running through them, attached at the bottom. Pull the lines, and the whole thing bunches up into the ceiling.
You say "
drop:" for a full-stage painted
drop, I agree that
traveler track is the way to go. Move it sideways rather than up and down. You can weight the bottom with a chain, and if you clamp boards on the two offstage sides and use ropes to stretch it out sideways (in a detachable way) you can get it looking pretty good. I did many a Nutcracker this way back in the day.
Drop #1 was on the
track and started the show in place and stretched. The stretchers were released and the
drop traveled off to
reveal drop #2 deadhung behind. Then at
intermission drop #3 was set and stretched on the
track (from the other side).