I'm skeptical about the idea. It seems to be reaching way too far and I'm not sure Larian has the capabilities to get it done. Especially since they're treating this as the equivalent difficulty cost as that of a skill tree, which is ludicrous. (Yes, I know that there's likely some inflation of estimated costs in stretch goals, but to price this at 150,000 is far too low to be realistic, imo.)
It also relies on getting the editor to the point where it's very easy to use. For D:OS 1, they hyped the editor up like crazy, and it turned out to be a tool only professionals could figure out how to use, and it was full of all kinds of utterly ridiculous restrictions, like not being able to edit or change Talents. TALENTS, ffs.
I'd need to know a hell of a lot more about how exactly they plan to get this to work before I could get interested.
What does "in-game-editor" mean? Does this take an existing dungeon and let players make minor changes, like monster placement and triggers and such? Or does it mean "you build the dungeon, room by room, item by item"?
This is also a multi-player only thing and absolutely no use in single-player. I really hope Larian's other games do not go this "Multiplayer-or-bust" way.
