16mo is a wonderful age! CSR is a beautiful resort. Transportation can be an issue at all resorts. CSR does have multiple stops. I've had great and awful bus experiences there, just like at other resorts. Ranchos is appealing to me because it isn't the last bus stop and you are more likely to have a seat when the bus gets to you. Casitas has the preferred rooms, though I do believe some of the buildings are also standard. Ranchos can be a bit of a walk to the front of the resort. I haven't been since the final updates, but it may be easier now with more bridges.
The new standard rooms are wonderful. There's lots of storage space. You can request bed rails for the bed, if you are worried about your daughter rolling out of a big bed.
The first time we took our daughter she was just about to turn 2. It was different than any other trip we had been on, but different in the best of ways. We didn't try to do everything. We skipped most of the thrill rides (I rode one and my husband rode another) and we didn't feel like we missed out on anything. Seeing everything 'new' through her eyes made for the best time.