Some good ideas here!
1. I would think Scirra will add this when they add a debugger.
2. What's wrong with the angle in the properties bar?
3. Agreed.
4. Objects are not rendered outside the game window at all. If you want to 'pause' the objects so that logic doesn't apply, that's really up to you.
5. Lerp?
6. I think it would be fairly easy to event this...
7. Agreed!
8. Also agreed!
9. This could be related to the previous suggestions, I suppose...