To answer my own question. Here is how I look at it.
Picking VPs are always a tricky business. There are a lot of things you have to jungle. For Biden, the big thing going against him is his AGE and worries that the Bernie Bros will vote for Trump or De Facto Trump aka Third Party or stay at home or write-in. We also have to consider Texas, Florida, Ohio, Michigan, Wisconsin, Minnesota, Pennsylvania, North Carolina, Georgia and Florida as key battleground states.
Freshman governors, senators, or U.S house members are probably a bad idea. He needs a candidate that voters can be confident of being a great president, just in case "old man Biden" gets ill or losing it mentally. Grisham and Whitmer are probably too inexperienced for Biden. They just won their governorship in 2019. Abrams came close to winning the governorship, but that's still a loss and wouldn't him his candidacy.
I am thinking Amy Klobuchar, Elizabeth Warren, Tammy Duckworth or Tammy Baldwin as the best candidates.
Klobuchar is somebody whose won over both Republican and Democratic districts and appeals to the mid-west.
Warren doesn't come from a swing state, but it would help him win over large factions of the Bernie Bros.
Personally I think he should go with a Tammy. Duckworth would be somebody with an inspiration story and would be somebody people could trust if disaster strikes again. Baldwin would be somebody to the left of Biden and comes from a swing state of Wisconsin.