I don't have any CL experience to share, but at WL the regular CL rooms are on the 7th floor, as is the lounge. Be aware that the Deluxe rooms are on floors 1-5, but do have CL access. To get between the lounge and the pool you would walk down the wing to the mid-wing elevator (which is at the end of the shorter 7th floor wing) and then head down. It lets you out by Roaring Fork, so then you go out onto the patio and over to the pool. Less than 5 minutes total, but not super quick.
Both pools are open, and both are fun to visit. The main pool is busier, but has a nice slide and kids splash area. The seating around the villas pool (Boulder Ridge Cove Pool) is more private but the covered areas are still first come first serve, and not rentals like at CR or GF. The walk to the lounge is a few minutes further to the Villas pool, because you either have to walk past the main pool and around the South wing or go out the lobby by the bus stop and towards Boulder Ridge and then down to the pool.
Here's a Boulder Ridge Cove Pool pic:
More pictures and information are available on the first page of the thread
here.
We have never done CL, but for us it probably wouldn't be a replacement for many meals, except maybe breakfast. We really enjoy the restaurants at WDW and wouldn't want to miss out on them. Whether the dining plan works out for you depends on how many of which restaurants you want to visit. I always recommend making a plan for where you want to eat and comparing the costs. For us the plan isn't a bad deal, especially if you can get a discount on it.
Congratulations on going in September. We love that time of year, and will be there this September as well from the 6th through the 15th!