The first thing is no problem and already implemented. But I would call it "Start+Pause Mode". As I implemented it I regarded a "stop" function as useless , because you can either pause or do a reset.
The second thing can be done by the simple brightness applet. But I think it could be easy to integrate the request functionality also into push-it. But it is not really the linux/kiss approach. But not complex anyhow.
I hope I find the time to also implement that and then build a package. Hopefully it will be in extras-devel this evening, if not my deadline is this time next week .
But if you would use the rubics rube of the ovi store, you would not run into the screensaver problem . But I dislike the rubics cube game on the N900. I prefer the mechanical version.