Ten-Hex brought it up earlier, but a lot of people seem to use the term "min-max" inappropriately. Min-maxing is the art of maximizing your advantages while minimizing your disadvantages. A true min-maxer would never take the Uncouth quality. He would take a Charisma of 2 and the influence skill group at 1, to be functional in basic social interactions. The only people taking uncouth would be naive new players, munchkins who play the game like a first-person shooter, and role-players who are genuinely interested in playing someone who has problems with social interactions.
On Karmagen:
It tends to create weaker awakened characters (which might be a plus for GMs who feel they are too powerful). Special Attributes in karmagen fall under the maximum allowable points allocation (in other words, a human can only spend 375 points on all Attributes, including Edge and Magic or Resonance). Also, the limit of one maxed-out Attribute includes the special Attributes in karmagen. So for example, a human couldn't have a Willpower of 6 and Magic of 6.
It flounders with Metatypes at the end of high Attributes for things like trolls, and is not really suitable for things like AI's, free spirits, or infected.
Where it shines is dice pools. Higher skills and Attributes increase at an exponential rate, instead of a flat one, making high dice pools more expensive. This is a good thing, because high dice pools are worth more. Karmagen does not force weaker characters. You can still make an optimized character, and will generally come out ahead, with a few extra points for skills or contacts. But generalists suddenly become more viable. In build points, if you make someone with average Attributes and skills, you've simply spread yourself too thin. In karmagen, you will find that this makes your character cheap, cost-wise, letting you spread out and get lots of those low-rated skills. A specialist converted back to build points will be a bit over 400 points most of the time, but a generalist converted back to build points will be way over. But that's all right, because the generalist is not overpowering. His low dice pools should be less costly than high dice pools.