I don't think cardigans are any more difficult than a pullover, and making a button band isn't that hard either. It's more tedious and a pain in the hiney and something you might have to do more than once to make it look nice.
At least that's my experience.
For your first cardigan, you might want to try to find a pattern where the button bands are knit right into the pattern so you don't have to pick them up and knit them on later.