I'm a bit of a fan of Ambrose, so I was happy to see him win it, but I also agree that he is somewhat limited in the ring in ways you don't want the champ to be limited. That said, from an objective perspective, I think it makes sense to cement the dominance of the Shield by having each member have a title run so shortly thereafter.
Now that the set up the triple threat for Battleground, I think there is a sensible way and motivation for having each man win the title:
Least Likely - Roman wins. The only way Roman can possibly win is a full blown heel turn. If he takes the title from Ambrose, it will only mean more heat for him. If he is still able to be rehabbed as a face (doubtful) this would kill it. Having him align with HHH to screw Rollins out of a pinfall on Ambrose makes some sense, allows Rollins to make a face turn, and turn the Roman hatred into great heel heat. (Not likely as they would not have booked Ambrose as getting in Reigns' face tonight, and I doubt Vince is giving up on Roman).
Possible - Ambrose Wins. This happens for one reason. Ambrose is over as hell, and WWE is immediately going into a brand split. Keeping the title on Ambrose for a few months on Smackdown provides a fan-interest anchor. Also, it may explain the early use of the triple threat...which allows for fluky pinfalls that have less negative impact on the guy who takes the pin as a one-on-one. Result would be Ambrose squeaks out a win, and has a few successful feuds with the likes of Jericho/Wyatt before Owens takes it off of him (Ambrose and Owens have great chemistry, so Ambrose is a good transition to Owens).
Most Likely - Seth Rollins wins. If WWE wants to put Seth back in the top spot, what better to beat Reigns at MitB and Reigns and Ambrose at Battleground. This would then lead into a rematch feud with Ambrose, which is the feud that really elevated Rollins after the Shield breakup. Ambrose can likely stay over as a tweener, which may allow the WWE to continue to pivot Rollins into a face role.