CMN is quite boring other than the impressive Mosque by the sea, RAK is very vibrant culturally, also this deal is available to RBA which I found to be very interesting with a few things to see. So depend on if you have 2 or 7 days, I say maybe do RBA for shorter trips, RAK for longer trips. Also can do open jaw CMN in RBA out, for example, two are connected with hourly high speed rail.
I have RBA and CMN on my channel linked in signature thanks to the AA F fare, but I have also visited RAK and can highly recommend it for culture buffs. More time can be spent in the Atlas mountains.