Tim Walz is by far the best candidate out of the shortlist however He's not a centrist (or not moderate and corporatist enough) so shapiro will likely be the pick.
This country is too centrist, too corporatist and too zionist for its own good that VP picks have to be strategic rather than a selection of the best candidate period
That's why Obama picked Biden to help him get white centrist vote and Al gore picked Joe Lieberman for the same reason
It will be Shapiro, unfortunately