I don't necessarily expect it to be supported indefinitely but they only just got the hardware into backers hands and are now taking in a lot of feedback so I don't think it unreasonable to expect some reasonable improvements in the shorter term.
Time will tell though. Personally I'd be quite happy with it after some bug fixes and a few small features. And if worse comes to worse it will become a personal coding project for myself.
Haha I think it's plenty durable so long as you aren't dropping it all the time.
The rattle is probably just the side buttons which do have a little wiggle due to the tolerances of the case.
The touch wheel on my was a little loose too which was a know issue. I just put a little piece of double sides tape on the top between it and the case and now it's all good.