Making NPCs into classes completely against type

Hey guys I've finally gotten some time to play through this and I thought it would be fun to mess with the NPCs classes using BEEkeeper and than I thought if I'm doing that I may as well make it funny by assigning classes that go against the characters concept.

ie. Minsc the Sorceror or Imoen the Barbarian (stats adjusted accordingly)

I was just wondering other than their classes not fitting them (which is the point) will this ruin the story in any way beyond being funny?

Edit: Oh and please avoid any spoilers :)