The thing is that if I'm going to a fresh new world I'm leaving the other one for good because I don't see the point in switching between characters and worlds. At first I didn't plan to make any other world or creating a new character. In RPGs I personnaly like to have a characters stats maxed in the end and do everything I can in the game with only one character. Also gaming time is precious to me and even if it's dumb, I'll feel like the 100h I spent leveling up were played for nothing.
This said I'll probably make a new character because maybe I shouldn't take it too seriously ^^
It's also hard for me to lose any kind of progression because I'm usually not into multiplayer/craft/survival games