Excellent description!!! Now I get it how this works, Thank you very much.
PS4 here - have 100% the base game in way of the strong and that did not unlock more than the intial 3 regions in way of the demon. Have also done most of the DLC. guessing at this point I need to complete main missions in way of the demon to unlock the next regions? was quite annoyed that more didn't unlock after completing it and DLC missions as thats how it unlocked more of way of the strong. That is convenient tho if all you need to progress in each greater NG+ cycle is playing the main missions, as some of the side quests are just super annoying.
update: as you fill up the game progress bar more regions become available in WOD, which is nice, but good farming missions like maraboshi aren't available until their usual time in the playthrough (after queens eyes maybe? or demon king?)