1. Full Associative between the Folded and Unfolded part. Can model on which ever makes the most sense at the time and have both update automatically.
2. Also the ability to change features at will (ie change a round louver to a lanced louver af design is complete).
3. Use 2D (dxf, dwg) geometry to use for bending, features, etc...
4. An automatic gusset feature would be nice for across bends. (Help: could be a extended shelled rib)
While your on the subject.