Not been using GE long so I'm sure I'll come up with more as I get used to the package. Not sure if the first two have been mentioned before but here goes ...
- Personally I'd love to be able to have more than one script window open at a time, in fact I'd like to be able to have more than one game project open at once so that I could copy and paste stuff from one to the other.
- The ability to set collision actions against multiple actors at once (instead of one or all)
A couple of echoes from me too:
- Definitely need more copy and paste functionality in general, Actors etc
- The ability to number of points in a path after creation would also help greatly