When you think which states the potential 2020 Dems would win in the Primary... Booker likely will be hard to beat in the Primary (esp in a crowded field). He would likely carry all of the Southern States + NJ & NY (and probably a heavy favorite in California).
If he did win- He would likely need a VP from a land-locked State... and maybe one with Military Experience (or someone on Intel & Arms Services Committee).
This depends heavily on which other candidates run. For example, if Booker is up against Kamala Harris and one or more of Andrew Cuomo or Kirsten Gillibrand in the primary (all people considered somewhere between likely and very likely to run), the advantages you note disappear for pretty obvious reasons.
