I fly about 100k miles /yr. Upgrades, preferred seating and premium services are important to me.

I am 1k Star Alliance with a good mix of international and domestic flights. I'm happy with United for international but I often need to use either US Air or Delta to travel from the northeast to east coast or midwest where United flights are less convenient. Now that US has left star alliance I'm flying 'back of the bus - boarding zone 15' far too often.

I'm thinking about splitting my loyalties to stretch to at least one 50k and one 25k (possibly 2x50k statuses) .

1) If I'm going to dilute my star alliance status am i better off with Delta or US/American?

2) I'd love to see a 'heat map' with red, for example, indicating a lot of flight-seats into an area with other shades indicating fewer. Something other than a route map showing lines everywhere with virtually all airlines to all places - almost filled with lines. I have common destinations such as Detroit or Philadelphia or Cleveland or Atlanta that i frequently travel to.

3) Does One World or Sky Team have the least overlap with Star Alliance on US (domestic) flights?

Figuring out the best FF program to earn status on for my common domestic routes isn't so easy! . Thanks in advance for your thoughts!