This isn’t just a console feature but I only own an Xbox copy of the game.
My idea is when you beat the game on hell it would open up a new mode NG+ where the player count and monster density is increased.
Every time you beat the game on a NG+ level the player count would go up by 1 every 3 NG+ levels the monster density would increase. You maybe would also be given a special icon or border on your character portrait showing the highest NG+ you have beaten.
If playing with others like in an 8 player game the player count setting would be 9 on NG+1 for example.
The MF bonus would still go up every 3 players and maybe there could be special items like uniques and sets you can only find on NG+ maybe some NG+ only runewords perhaps even a new item quality like mythic gear. Or maybe mythic versions of existing uniques.
I think monster resistances should go up but only every so many NG+ levels and only to the point where a sunder charm is no longer breaking immunities on high NG+ levels.
You would start in act 1 and for balance reasons you would be given different quest rewards such as gold, xp and maybe unique gear for quests that give skill points and quests like Anya that give resistances.
If it’s possible to increase the level cap I think that might be fun for NG+ then maybe you could still get regular quest rewards for most quests. If you are able to have extra skill points I think that they should only be available in NG+.
Terror zones would scale to the NG+ level as well. You would have to beat a NG+ level to unlock TZs on it.
It might be a good idea to buff mercenaries while in NG+ but then again if you can get new powerful gear in NG+ maybe mercs wouldn’t need a buff.
When making a game you would choose your NG+ level. I think 8-16 NG+ levels make sense.
I think this could be really fun and challenging as well as give another good way to level up to max level. It would also give another goal for ladder as now in addition to reaching max level the race would also be to get to the highest NG+ level.
I really want to develop this idea so any feedback is welcome. Feel free to say what you think is good or bad about the idea. I think this could really be a great addition to the game if done right.
I will likely add to the top post any changes the community comes up with.
Go hardcore, you will have to adjust the way you approach everything, try to complete the game naked (no gear, just skills) and there are various other ways popular streamers came up with just to challenge themselves.