I haven't really had that experience. I fiddle around with character creations a lot, and most of my optimized ones come out worth more than 400 BP. And that includes paying for the knowledge skills that I would normally get for free under BP. Generally, a min-maxed karmagen character will work out to be the equivalent of 450 BP, give or take, while a non min-maxed karmagen character will work out to be quite a bit higher than that.
Karmagen doesn't so much punish min-maxing, as reward generalization (because low skills and Attributes cost a lot less). Well, kind of rewards it. Dice pools are still one of the main gauges of character effectiveness, so characters that are spread out a lot are still disadvantaged, even if their character can have a lot more of these low-rated skills than they would in BP.