Agreed with more content, level 5 is needed.
I hit level 4 around the blight village.

Level 4 don't inspired me to do a dual class, most level one skills are useless in the underdark.
I would like a Sorcerer lvl 3 with wizard lvl 2 to make use of short rest.

I think one major update for each missing class ( Monk, Paladin and Bard ), with level 5, karlach and balancing the game ( headband of intellect at 17 :'( )