I've only stayed at POR and All-Star Music. With 5 people, POR is our most economical choice. The pool there is fine--my kids (5,7,9) loved it.
There are many details about the OP that we don't have... how many people? Ages? length of stay? Touring style?
We go to the parks pretty much from open to close. So, it's really an effort to make it to the pool. We don't do a lot of hanging around the resort (no time in the morning, and too tired at night).
I don't know that any of them have a slide that I would consider very exciting...
If you want to spend a lot of time at a pool and experience good slides, you might want to check into the water parks. We loved Typhoon Lagoon... Spent a fair amount of time just playing in the sand. Well, as I said, there's lots of missing info, and what you would choose depends on a lot--from personal preferences to practical concerns.
As for being "run down", well, maybe you're just seeing the theming. POR is designed to look like mansions on one end and slowly progress to bayou shacks on the other end. It's a down-home, Dixie kind of feel. So, it intentionally has a "rustic" theme. HOWEVER, just because it's intentional doesn't mean that it's "your thing". So, again, personal preference plays a part there...
We enjoyed POR for the small amounts of time that we actually spent at the resort. The food court is nice--a number of choices there. Also, if you're on the dining plan, it's a great place to use snacks for milkshakes:slurp:. Also, it has an area with a TV, crayons, etc.. So, the kids can go mess around while you eat in relative peace...