Harris is a new generation of politician but she has Biden-esque favorables. Dems would arguably be better off with a popular purple state governor (Whitmer, Shapiro, Evers, Polis, Beshear).
Sorry, but if it's not going to be Biden or Harris, it has to be a Senator with a lot of cash on hand or we're giving up a ton of fundraising. (We would be giving up a ton of fundraising because I am pretty sure you can't transfer Biden's COH and if it's at the convention you lose double dippers)
For the record my opinion is
1. No evidence Biden should drop out at the moment.
2. IF he does, Harris is the clear replacement.
3. TODAY I'd rather have not Harris but maybe her favorables change.