Still on 7.2.95 but just checking in after a little over year to see what's up. On first read here's is my two cents opinion:
1. One container solution is simpler and less moving parts to break. The unknown is an unestablished container developer?
2. Two containers solution sounds like it would be a nightmare for casual users (like me) to keep updated since there are now twice or more moving parts to worry about. However, the containers are maintained by established developers.
Operating under the KISS mantra, I would prefer a one container solution. Let's put it this way, if I was brand new to Unifi and looking for a way to run it on unRAID as a docker container, I would most likely opt for the one container vs the two containers solution.