Better half piece/pitch and corner support
These are great additions, but I've noticed that half pieces don't snap around in all orientations (top vs. bottom, left vs. right), they don't burn reliably either and they obstruct weather effects more than they probably should.
Half pitches need corner options. Also, regular corners need more placement options if possible, I've noticed you can't make a diagonal ramp by playing 2 corners together even though it looks physically possible.