A Fifth Hero (or 2nd Builder Hero)
What about a fifth hero, or more realistically, a second hero for the Builder Base?
The Wizard King is something we've seen time and time again, like the image above. And, we don't have a wizard or spells in the Builder Base yet, so that could be a good middle ground. A few leaks and rumors in 2019 said we would get something known as the "Reviver", which could be cool.
I think we'll get a second powerhouse Hero in the second village sometime soon, and a 5th hero for the main base just seems excessive and overboard. That said, based on previous release cycles Supercell very well could add a 5th hero to Town Hall 14 sometime in 2021.