Cypress Harbor has 3 pools. One a smaller, quiet pool. Two larger ones. I don't recall any slides. One has a bubble area with bubbles coming from the bottom of the pool.
Horizons has one pool so far. On one side is a pirate ship with one or two small slides on it. But these slides are really for younger kids. They also have a separate water play area. The kind with water guns, and big buckets that dump water on people. They also had a really nice mini golf course, although is wasn't free. I believe you could either pay per round, or buy a pass good for the entire family for the length of stay.
I don't recall the pools at Royal Palms, Sabal Palms, and Imperial Palms very much. I think they tend to be regular leisure pools. However, as spiceycat mentioned, these resorts have access to the Marriott Orlando World Center hotel pool (on the same grounds). Don't recall if it had a slide or not. (Probably did). It did have waterfalls.
Grand Vista has at least 4 pool areas. Two are of the leisure pool type. Two are more elaborate with multiple pools. The one I spent the most time at did not have a slide. Didn't spend much time at the newest pool area, and can't recall if it had a slide or not.