blending

I've got many a gallon of cider in bulk storage. We're getting close to that 6 month mark, and after testing ph, so2, and taste yesterday, I'm becoming increasingly incapable of waiting too much longer before bottling up at least some of what I've got from last fall. In any case, this is the first year that I've tried to be a bit more exacting in my production, so what I did was ferment each type of cider separately. Now it's time to think about blending. Here are the varieties that I have:

Jonathan
Jonagold
Rome
Golden Delicious
Arkansas Black
Granny Smith

I'd love to hear what anyone has to say about how to blend these varieties, ratios, etc.

These varieties together prior to fermentation probably would have given you a much better balance cider. Some of those varieties by themselves do not have the nutrients to ferment well without adjuncts. It sounds like you have a very good blend of apples for a proper cider. Tannins, acids, and sugars all work together to keep the yeast happy. Happy yeast = happy drinker.