More than a decade ago, a friend asked me to design an alarm clock with a f ew features similar to what you describe. I threw something together in an hour, and he rejected it for one of the reasons you've mentioned (display too bright, or whatever). So I tried again. And failed. And a decade lat er, I still like to throw a few hours at the problem, because it's so absur dly simple that I can't solve it.
I would like to suggest a feature for your clock, though: DMX. My friend asked for, among other things, a dawn simulator which would fade up room li ghts. I found, after several iterations, that theatrical lights are cheape r than anything I can build:
They're controlled by DMX, which is basically just async over RS485, so it' s trivial to through a spare UART into an RS485 transmitter for a couple of bucks, just in case. Of course, you have to run unsightly DMX cables arou nd the room...