stupidity where stuff gets double-added to entity list
replace linear search through IdLists with faster (binary search?)
point face distance constraint

STL check for meshes, and T intersection removal
STL export
better triangle combining (Simplify()) for meshes
solids of revolution
investigate slowdown with large number of entities
DXF export
compress file format (binary?)
partitioned subsystems in the solver
arbitrary color specification
TTF font text
display with proper formatting/units
more measurements
reference dimensions (just to look at, no equations)