Glad you have lots of time. I think you will quickly realize that there is little point in stopping in half the states in the US. Why would anyone want to stop in Kansas, Nebraska, the Dakotas to name a few. Depends on your time frame and purpose I suppose.
My trips would be more the north south thingy. Start north in Canada around July 4 slowly heading south down the East Coast to the keys. Then across to New Orleans and start up north through the middle in March/April arriving in Michigan/Canada/Wisconsin around July. Cross through Canada to the Rockies and then south to Padre around xmas time. Then up the California coast eventually arriving in Alaska around July. Sell the RV in Alaska around September 15th and fly to Hawaii to winter.