Can we have that option please? I don’t want to beat the boss then come back to started area to farm resource then killed by a random mob
If i am not mistaken, the mobs dont scale with level.
(AFAIK this is even a design decision of the devs because this destroys power progression)
There are, however, new mobs if you progress in the world, i.e. trigger specific events. If you do not want that, you could try to progress with the quests slower, or create a new world where the events are not done yet.
either way they are too bad for me (maybe others). One hit die (or 50% health bar) at starting area won’t be a good feeling. A select-able option is better choice
I think it is more of a balance problem.
Right now it feels like at the start you are hit by a truck, but with progress, especially better gear everything becomes much easier. I think it should be more like the other way around.
Btw. I just re-started a character so this opinion excludes player skill increase. I still think my lvl 5 character has it much much harder in the first area, than my lvl 25 character in the last area. And now i know how to block, pary, dodge (and avoiding bugs) 
And… 10 points in health are a blessing