Both Bryce and Zion are spectacular. If you have access to a longer than 80mm lens I would take that plus the 50. Personally, I am satisfied with B&W so I took two Hasselblad bodies, my 50 and 150 plus a 2x. Ilike to have both loaded with the same film (Ilford Delta 400 -- depth of field is important to me) as I like to stop down. A light but sturdy tripod is a must. I'm not keen on polarizing filters but I took a yellow, orange, light orange and light green. A spot meter and cable release. Carry all in a camera backpack if possible.
Bryce is high desert going down into the canyon is easy but remember ... he who goes down also has to climb up. Especially in Bryce I suggest getting up before sunup and catch the very early light. It is almost like going to another planet. If you have the time Capitol Reef and Moab and environs are also great. We have been out there three times and I would gladly go again. Do some internet research if you have not already done so. There are MANY wonderful sights in that general area. The drive from Tropic to Torrey through the Escalante Preserve is one of the best scenic drives in the country.