I'm basically preaching to the choir here, but what the hell...
Choils. Forget em. Well, maybe one thats a few millimeters wide to make sharpening nicer, but I want to hold onto the part of the knife designed for being held.
Bad geometry. Sadly every Busse I actually use had to be reprofiled & sharpened right out of the "box".
Poor balance. This is mainly an issue with smaller knives seeing as with big choppers being forward heavy is just fine, and medium (7") knives naturally tend to be neutrally balanced, but with small blades I'm sick of overweight, handle heavy knives. Again, out of my collection this is mostly an issue with my Busse's, big handles, thick steel, heavy micarta/g10 handle material and no skeletonized tang. I can't imagine that skeletonizing the tangs like the BRKT Bravo 1 would cost much more to make seeing as it's all done with laser/jet cutters, but it sure would improve the knife.
Long handles. Now this is a matter of personal preference, but I'm not a fan of excessively long handles, I like them thick and full, but not longer than necessary. On small knives especially I always want to hold the blade as close to the edge as possible, there's no need to "choke back", and some of my knives could stand to have 1"+ cut off the butt.
It seems that Busse's are getting a fair bit of criticism here, but that doesn't really surprise me given the inherit issues with a lot of their designs (choils, geometry, ect) and the high expectations that are set out by the price and hype they receive.