Regarding the ranger:
I still do not understand why Minsc is a ranger.
From his behaviour and his job (bodyguard of Dyneheir) he feels more like a barbarian.
Especially after playing NWN2 MotB where we meet witches and barbarians.
Maybe they made him a ranger in BG1 because there was no barbarian class and they kept him a ranger in BG2 for consistency.
Pretty much that, correct. Though in theory they could have used the appropriate kit from the "Complete Fighter's Handbook" at least for BG2.