This is what you said,
So, say the next tiers of gear are 81 and 83, the layout would be:
New mythical HM Op - drop set bonus gear with lettered 83s
NiM - drop set bonus unlettered 81s
Comms - buy non-set bonus, lettered 81s
Did 81s become better than 83s at some point?
Not to mention you say to allow comms to buy NiM tier gear.
Anyways, carry on.
Unlettered 81s would be better than lettered 82s, yes. Whenever the new HM drops it will have better gear than NiM..just like HM DF and DP are better than NiM TfB/S&V. They basically make the NiM pointless as far as gearing goes. And you can buy better gear than the NiMs currently with comms as well. If you can buy the same tier as NiM with comms but only lettered then comms would buy gear behind what you could get in NiM and HM...the way it should be IMO.