This may be an obvious statement, but there better be some sort of educational partnership with the Riverkeeper, SJWMD, and potentially the Florida Springs Institute; especially if there is going to be an aquarium. We need to educate people/children on the interconnectedness of the aquifer, the springs, our waterways, and climate change in order to make smarter decisions in the future.
I'd love to see some sort of outdoor tidal exhibit on Hogans Creek or the banks of the river, an aquarium modeled after the springs with the proper inhabitants, and a wetlands exhibit featuring mangroves and grasses mimicking the keys and everglades.
Agreed that various groups should partner on this and there are many good options. JU's Marine Science Institute would also be a good partner. A REALLY big opportunity is to get OCEARCH to relocate their fleet to the site and create and exhibit. I believe they are currently at Mayport Village. They have a global following and might actually pull some people off I-95.
Along with Hogan's Creek kayaking, the other big ecotourism opportunity I see is to finally do something with Exchange Island. For such a big river, there are laughably few destinations for boaters. I live in the one of the best areas for offshore boating in the state (Jupiter), but there are still tons of cool places to boat inland. There are several places along the intracoastal you can dock and hike preserves at, numerous sandbars, and some great island parks. Peanut Island in the intracoastal near West Palm Beach would be a great model for Exchange Island. It's kayak and paddleboard distance from land and attracts tons of them, but also has docks, beaches, and sandbars for boats. It has some of the clearest water in the state and great snorkeling, so not totally analogous, but would still be a great model. It has camping, trails, fishing, hiking, and numerous picnic spots and pavilions.
https://discover.pbcgov.org/parks/Pages/PeanutIsland.aspxIf the new MOSH wants to have a conservation/ecological focus, having the opportunity to offer boat tours, kayaks, and paddleboards to Exchange Island to get a feel for the wild St. Johns would be a big draw there and to Downtown in general. We used to do overnight sleepovers at MOSH as a kid, which was cool; but imagine doing stuff at MOSH all day and then taking a boat to camp out at Exchange Island. Of all the screw up's Jax has made related to Downtown, not taking full advantage of Exchange Island is up there as one of the big ones. If Mosh is going to the Northbank, it would be the perfect time for Jax to make an investment there that would not only benefit the general public, but also provide a huge boost to MOSH and downtown.