I think you are asking an interesting question. I am seeing growers of vinifera in your part of the country struggling with vinifera. Temperature in winter or ripening period seems to not be a problem. The problems arise with the humidity and rain. It seems that even with intense spray regimens, many are barely winning the battle against mildews and other diseases. I am in Northern Illinois, and grow Petite Pearl and Verona. We have very high humidity and at times similar rain patterns as well. I spray with Mancozeb and sulfur until July 1st, and afterwards basically nothing, and have never seen a hint of disease. There may quite well be good reasons to avoid vinifera and experiment with hybrids in your zone. Vinifera seems to do well in a Mediterranean hot dry climate, semi desert areas . Purchase some Marquette and Petite Pearl wine on line and see if you like them, you might be surprised. There is a reason the wine industry is rapidly growing in the upper Midwest. You mention insects. The only insects I have to deal with are Japanese Beetles a few weeks per year.