I think the level 20 will come with the second game, since D&D is capped at 20. At least I hope so. I like games where you pick your character from the previous games, like BG2 or PoE2 =D
Well it depends. If this games takes you up to 14, leveling up only 6 times in the sequel might feel as if there isn’t enough of a progression curve for a full sequel. I could see 12 to 20 working, though.