Just like many German lager or lager-like beers, there are few hop flavor or aroma additions in a Kolsch, so you might just want to keep most of your additions at the 60 mark with whatever noble hops you feel like. But since you call it "Kolsch-ish", you're probably free to hop it however you'd like. The grain bill seems pretty complicated too...for a Kolsch at least. Kolsch's are pretty much 100% pilsner. When you add other types of malt or adjuncts, you're heading into blonde ale territory (as long are you're in the SRM range), but again...kolsch-ish...pretty much leaves it up your imagination.