You can literally just switch the bottom part of the trees for new Keystone talents and passives so the basics of the class stays but still give some new way to play. Or just switch the class ability.
For instance if Vet ever gets the machine gun the dreg/scab gunners are using they could add some talents that work with them on the side, like they did with Psyker when they added the melee and staff talents.
Honestly, thatās just to the player to deal with, traversal cost can and should be used to balance builds (yes I played PoE)
Okā¦ you ask few new talentsā¦ that, I think it will happen.
But tbh, will it renew the gameplay? after 2 years, I am not sure.
Anyways, I actually play AC shadows that I enjoy to play as it is soloā¦ and soon we will get Dune that I await badly.
I just give my opinion, but fact is that, for me, this game is going wrong. Balance is broken for too much timeā¦ Ogryn rework has not rebalanced thingsā¦ I would even say that this is the contrary.
I donāt like how they threat now the difficulty, throwing 12 589 specials and elites in one missionā¦ and now that it is not enough, nuking our stats with hidden modifiersā¦ I donāt like havoc, I donāt like the current balance, and I donāt like their proposition about the difficulty in this game.
To say the least, a new archetype could revive my faith in this game.
Donāt get me wrongā¦ I appreciate Darktide. And even more than I should considering how many things annoy me. 
At least AC Shadows is great! And next month, Duneā¦ few chances that I adopt the game, but the universeā¦ wowā¦ I want to play it just for the universe.
The thing we need most is a new biome with vastly different visuals.
That will feel the most refreshing in terms of content. Totally new areas of the planet (with plants?!).
Something to make the soup a bit more varied.
Iād still pay for a rattling though 
4/5 characters created might make you think there will be another class but the class overhaul update killed that potential. sadge
when we see SOLO mode we wll get new classes!
So, somewhere between now and the heat death of the universe?
I donāt really think the 5th slot can be pointed at as hint toward new class/arche, but on the hand, we do know that back end, āwe haveā 8 slots, with only 5 accessible, it make more sense that if theyāll add one, theyāll add a new slot alongside it.
Though again, not likely (and Iāve been saying it since launch, the 5th slot was there to be able to try other personalities and gender without deleting your character, before Butcher had the reset thingy)
Logically, a fifth class will come, I think they have planned it from day 1. I think maybe this year.
Why do we have 5 character slots anyway (or 8 Server-Side usable with the more characters mod). I guess they laid the groundwork for this, but postponed it indefinitely.
so soon?
Probable if we get a new class, it will be anounced in a month or so at skull event
I like these ideas. I love the banter, I would like to see more of it!