In an ideal world, all those existing Ray fans in Tampa could take a Brightline on a discounted price (or free with ticket on certain days) from Tampa to Orlando when they finally build the Brightline expansion. They currently do a similar program with the Miami Marlins... so it's doable.
Yup - as it currently exists the area can't handle it. Aquatica and sometimes SeaWorld will backup the existing roads with traffic on busy days.
Once Epic Universe opens up (and the area fully develops with additional hotels and the Catchlight project)... they probably won't be able to accommodate a stadium there without major infrastructure work.