We stayed at the Poly before we had kids and NOTHING beats staying on the monorail. That being said Poly is also way more $$$.
We always rent a car, so I have no idea as to the wait for the bus. My logic is with my dd3, when she is ready to leave, she is READY to leave. The last thing I want to deal with is a meltdown because we missed the bus. We are going in Dec for 9 days and I got a car for about $200. My sanity is worth $200. If you are willing to spend the money on a deluxe maybe a car is something to consider.
We had the
AAA diamond parking pass so you park right behind the handicap section and did not need to take the tram. You didn't hear it from me but you can buy the AAA parking passes on ebay for about $20. If you are renting a car, get one. Especially with kids, strollers, etc. SOOO worth it.
I'd say from MK back to CBR was no more than 1/2 hour. That included monorail, walking to the car, loading everyone in and drive. The drive itself is only 5-10 minutes.
The 1st half of the trip we would go back to room around 2:30-3pm. You can buy sand toys at the CBR giftshop, or get the kids chicken nugget meal the 1st day there. It comes in a pail with a shovel. I think the sand toy bag we bought was about $10. Had lots of stuff. We would bring the sand toys, some snacks and a few "adult" beverages down the beach and just play for a bit with my daughter. She loved it and it was very relaxing for dw and I too.
2nd half of the trip we couldn't get my dd to leave the park so we never made it back to the room. We kind of "missed" our afternoon break.
If you have any questions about the CBR just let me know