I’m working on a similar idea to yours s i’ll chuck in my two cents on this… I’ve bought acrylic and read others say i should have went with glass… I absolutely wish i had.
Your glass in front of it might protect it, I read larger pieces of acrylic can warp… Mine has a bit, its ok if you are sitting in front of it, but if you look from a distance its not great.
I love my mirror and frame ( used some wood and stained it ) but my biggest regret is not going for glass. I’m trying to get the PIR sensor to work properly - I’m not there yet, it seems to be very sensitive and wakes up a lot… but that’s probably because i’ve not got it set up quite right…