The only feature we are really missing from the old days using Photoshop is the batch actions feature. The ability to run changes on multiple files at once in a batch.
Appreciate it isn't a simple feature to add in.
Apart from this Affinity Photo is far superior to Photoshop in speed, features and usability. It has sped our teams up significantly already. I can't express enough how appreciative we are at the awesome job Affinity have done releasing this program, it's exceptional.