I would agree starting at level 1 would be ideal when starting a new adventure, especially in a video game. But I would humbly disagree 10-12 is an ideal "end of adventure" point. I am not saying you are wrong, and level 12 nets a lot of classes some nifty features, but I just dont see why you wouldn't use the full range of levels available to you. Especially when we are talking
going to the underdark, fighting against an organisation with reach(cult of the absolute), going into the hells ect
.
As you said, stopping at level 10-12 leaves room for a DLC/Expansion that takes you to higher levels but DLC could easily be new adventure packs/races/subclasses and the like so we can have other (perhaps smaller) adventures via DLC/mods. In my mind, not having the full range of levels available from the start (even if the campaign ends at level 10-12) is diminishing the potential of the game and its longevity.
I dont mind giving Larian my money, but leaving out content from the original source just so you can add it in a DLC feels.....well....very Electronic Arts. I'd prefer the DLC be classes/races/new adventures rather than "WE RAISED THE LEVEL CAP".
Ofcourse, this is just my opinion and I am quite bias lol.
