Wow, this post didn't get any love the 1st time around, did it?
I'm drinking a Pyramid Curve Ball right now, that's how I found this thread. I've never had a Kolsch before, I've been looking for a commercial one to try - but Kolsch are hard to find in Nebraska, go figure.
A: Pale yellow honey color, soft pillowy white head. Very clear.
A: Yeasty, sweet, malty, but very faint. A bit of herbal nose, I suspect this is the Kolsch yeast.
F: Crisp and light. Finishes with a bit of a starchy taste. Clean. Simple. Not overly malty, nor does it have much apparent hop presence. Just... well, frankly a bit transparent.
M: Thin, watery. Tiny carbonation bubbles that just "pop" as you move it around your palate. A bit of lingering pucker, but not enough to really notice unless you're looking for it.
Judging by this, I'm guessing there are no "herbs" in Curve Ball. Your recipe looks like it could indeed be spot-on for a Curve Ball, I would use the Wyeast or the White Labs Kolsch yeast as it should give you the best representation of the herbal characters you're looking for. Otherwise I noticed their website lists Perle hops - that may be the "secret" you're looking for, Perle has often been described as very "earthy" and "herbal" when used for bittering.
I think 65 should be spot-on for fermentation temp, and I think you are right for suspecting the need to mash low, around 148-149.
Cheers! I'm going to go finish this beer now.