Since the splash area is a must, my vote would be CBR. The walk between POR and POFQ could be long if you're in the far Alligator Bayou section of POR, and the path is in direct sunlight. Its doable, but not ideal IMO.
Other than that, CBR has the Skyliner to Epcot and DHS which is a game changer for us. A huge pro. The biggest con here would just be the size of the resort, but the new configurations after the remodel has helped it feel more manageable. At POR, they have the boat to Disney Springs which is a nice alternative, but not necessarily any faster than the bus. You can't go wrong at either resort, but with the splash pad and convenience of the Skyliner with two toddlers, CBR makes more sense.