Agree on the backspace. Especially, since left arrow does that. I constantly hold backspace and expect it to advance automatically.
Speaking of features helping investigating/monitoring complex scenes:
Another feature I suggested to @tehn was the ability to continuously monitor variables and values in the LIVE mode. Right now you can punch a variable name and it will only display the value of that variable, at that one moment, which is helpful, but very limiting. I find myself using arrow and enter keys repeatedly to do fake continuous monitoring of changing values.
It would be great to just enter the variable, and see the value in the line above updated continuously: super helpful in programming!
AND, if that was also not just the one value, but if the LIVE screen actually displayed upward scrolling last six entered lines, one could potentially set up a screen that would give a live display of several key/important values being updated live and providing extremely useful overview of the dynamic elements of the scene.
Anyway, both of these features in my mind would make the Teletype even more of an instrument, where the code is being “performed”.