For $15 more a day I wouldn't think twice: CBR. Larger rooms, far better pool for children.
You can pay a bit more for a 'preferred' room, if refilling your mug and being close to the food court/pool/nightly marshmallow roast and movie is important, but the farther away rooms are quiet and there are 'quiet' pools scattered throughout the resort.
Depending on the age of your kids, the CBR pool is far, far better: for younger children there is a fenced off pirate themed area just for them! Everyone else has a great pirate themed pool with slides. And the pool is right next to the food court, pool bar, evening marshmallow roast and movie. I think only teenagers would prefer the pool at Pop (because the slide wouldn't be exciting enough for them at CBR). Moderates have all the towels you want right at the pool.
I've never seen a snake at CBR, or anywhere else at Disney. Not saying they aren't there, just seems unlikely to be a particular problem at any one resort over another.
Yes, CBR has multiple bus stops. If you have a rental car, ignore that issue. If you are relying on the buses, well, its kinda hit or miss the amount of time you wait and number of stops to sit through. Its not perfect, but the bus stop for CBR at the parks is closer than Pop so, well, you save some time in walking.
I don't dislike Pop, but the benefits of CBR with kids I think are well worth $15 a day.
PS You can see the Epcot fireworks (a bit - the top 1/3rd of them I'd say) from the beach area near the preferred rooms/food court pool bar area. Nice when you are just hanging around the resort at night.