I did the same trip (minus the Grand Canyon) in Jan/Feb this year and, although Zion had a light dusting, Bryce was the only place that was properly snowy.
The whole route is a photographer's dream, particularly Antelope Canyon. I was a bit disheartened when we arrived there and saw how many people they cram in (it's basically a continuous conveyor belt of tour groups) but it's actually really well run with strict timings, and the natural bends do a fairly good job of isolating you from the other groups. Best to book ahead though.
Here's a few of my favourite snaps.
All of the above are on the agenda, I am booking to do the photography tour in Antelope also aiming to do Canyon X in the same canyon. Will be a few early mornings and after dark tours along the way.