This is an impressive map, but there is no reason to give away so much of Virginia. Absolutely none of the Shenandoah Valley should be given away. It is a very Southern region culturally. Just give away the three or four counties in the very north of the state that are clearly entirely suburbs of D.C. I personally wouldn’t give away any of West Virginia either. If this new country joins with part of Canada, it really should just join with the prairie provinces, as these are the only parts of Canada that are culturally and politically similar to us.
Similarly, California east of the coastal range is very conservative. The liberal part of California is a strip averaging about 20 miles wide along the coast. New York outside of NYC and the Hudson Valley up to Albany , and the coast of Lake Ontario (Buffalo , Rochester) is also conservative. The same for the Great Lakes states and Pennsylvania. Once you get away from the big cities, America is conservative. Look at the red/blue map of the 2004 election and they control about 5% of the land area. Don’t give them any more than they control now.