Pets Ahoy will likely be changed whenever their contract with Joel Slaven’s Professional Animals is up for that show (most likely). I'm not sure how much longer it's good for, but it can't be too much longer. SW will likely produce their own show in that theater , similarly how they've done at BGT with Critters Inn Charge.
A new semi-permanent show would be great in Nautilus Theater, something Cirque-esque again would be great (I say semi, as I'd still like a seasonal Christmas show in there like currently).
One Ocean's days are numbered and can't wait to see what they bring in to replace it, even if it is more "educational." It's been boring and stale for years IMO. I've only bothered to see it twice in the last 3 years, and that was only because I brought family who wanted to see it. Otherwise I've skipped it. 2020 seems to be when they may switch, but of course nothing official yet on an end date for OO.
Key West needs a revamp, badly. I see nothing wrong with putting some moderate family flats in that area as mentioned in previous comments. It's good to have attractions spread out a possible. The two rides they put in at SWSA this year with their Turtle Reef exhibit is perfect.
With other needs that the park has, I don't see a coaster again until 2024 either. Just because some of the other parks are adding back-to-back coasters, it doesn't mean SWO will or needs to. SWSD, for instance, is just starting to catch up to the other 2 SW parks in terms of rides. Both BG parks are known more for rides and thrilling coasters, so they are playing catch-up with themselves having been down for several years and being in a better position to compete again in their markets. BGT needs to focus on flats for a few years themselves, which 2021 looks to be a start at least.