1) Non programmatic collision modification:
An object's collision sound and sprite can be modified with script commands. To achieve this, the object has to be running a script. Seems inefficient to me. Shouldn't collision sound and sprite be object properties, like texture? Probably, we should keep the scripted ability and just add the ability to change these as object properties. Script command would, of course, have final say.
2) A "teleport back to last location" button:
Many times, you just need to pop out to the store and then you wanna pop back to the last spot you left (teleported) from. If you left from home, you can TP home. If you didnt leave from home, a TTLC button sure would be convenient. We have a "last channel" button on TV, right? Let's get one in SL. Maybe the system could do it by creating a "last location" landmark automatically, upon TP.
3) Ability to disable or customize mouse cursor changes over "active" objects:
The mousey cursor changes to a hand if an object has a "touch start" script. How about a script option to overide this? For exploration games, it would allow the game coder to make "hot spots" less obvious if the hand cursor was disabled. If the cursor was customizable, with a 32x32 image map or something, that would allow even cooler possibilities.