In my opinion, the number 1 problem in this game is that new players are vets are pretty much separated. The new release will make it even worse since new players won't be able to even get to where all the vets want to play (below emberlight).
So then the question is how to get vets and newbs to play together. I don't think it should be forced (i.e. making it so people can't get below emberlight whatsoever unless you go below haven) but rather encouraged. What's the main problem with how the game functions now? Below haven gives you barely any crowns/rewards at all.
I thought of this some time ago and posted it in the general forum once I think, but I don't think I posted it here. But essentially I think crown rewards should be even through all the zones. So if you make 500 crowns in a level below emberlight, you should (as a general rule) also make about 500 crowns in a level before haven. This not only would encourage people to play together but would make it easier for newbs to get better gear (they would probably have to balance out the prices a bit if this was ever implemented to maybe make items cost some more crowns).
So then the question comes into play, if rewards are the same, what reason would there be to go below emberlight? Why not just stay under haven? Well the answer to that is to make a cumulative system that rewards you more based on how many levels you completed. If someone went from haven to the core they would make a lot more money than if someone went from emberlight to the core. Of course not everyone has the energy to play 30 levels, so things can't be exactly even. For instance the farther down you are the more heat you should get, and the farther down you are the greater concentration of red boxes there are. Things like that. Also bigger and badder bosses would be further down that could have chances to drop phat loot (like how the turtle drops the 5 star turtle shell). But the important part is to keep the amount of crowns enemies drop to be relatively even or else people feel swindled if they play below Haven. The cumulative bonus would also be even. So if you played from haven to moorcraft you get the same bonus as if you played from moorcraft to emberlight. The idea is to not make players feel like they are wasting energy if they play below haven.
The cumulative bonus could be based on how many levels the player has played, or the team, or a combination of both.
Oh, and this idea works a lot better after they did the "equipment is worse the closer you are to haven" nerf incidentally.
Or you could make pay sort of "bound" to player experience?
To give an example:
Say you wouldn't gather coins, but instead some kind of impure mineral inside the clockworks and etc. Higher player experience would allow you to purify it much better, which would in return gain you more coins back at Haven where a mineral trader sits and buys these off players. With a system like this you could put the pay even at every depth, but just let it depend on player experience? So you still have the increasing pay throughout the game, but you get the same pay at every depth.
Just throwing something in!