Veep picks are made primarily on the basis of movement ranges.
Noob-trap though. Obviously, a high movement range is useful, when it comes to the nitty-gritty movement ranges have a lowish winrate for a reason. People ignore more important things like synergy with the rest of your campaign. The classic example is McCain having what I consider to be a fairly tanky campaign, but instead going with a hyper-aggressive VP pick that was more of a liability than anything back in the '08 tournament. Terrible choice: forced to spend a lot of resources on defending a magnet for enemy fire when the whole point of his strat was to survive Obama's significantly more fragile build and string it out while poking holes in Obama's defense. And a high point cost to boot. Plus Palin's preferred terrain was terrible; Alaska? And all this for what? Her hyper-aggressive attacks played well enough on their own, but since she didn't fit with the rest of the campaign she was forced to go on her own to do any damage, but that left her vulnerable to counterplay and let Obama dictate the terms of the fight. Palin would have probably been better with Trump, for example, since he runs a hyper-aggressive lightening fast build that focuses on dominating the playfield and not getting bogged down in "fact on fact" fights that he never wins anyway. Biden, by contrast, was another unorthodox choice, but he synergized well enough with Obama's campaign that Biden was brought back for Obama's successful "aggressive defense" strategy as the reigning champion in 2012.
In any case, never pick a VP to dictate the terms of the fight, which is what you want with movement range. The Candidates' intrinsics are what define the battle; the VP's have intrinsics too, but again, it's a noob-trap. The only important stats for a VP are whether they have (USEFUL) favorable terrain bonuses or they synergize well with your build. Other than that you may as well go for a safe pick than one that will require you to go out of your way to utilize and may well do more harm then good.