I like both the traits but somehow he has
too much focus on expansion and that is all he has riding for him. He makes for an excellent AI because that way the huge expanse of land he grabs goes to good use but as a human I find him lacking. My predisposition may have to do with the fact that back when me and Silu played Co-op we always ended up against Joao + friend (Shaka was the usual suspect) and a 20~ some city Joao boosting a wardog isn't that much fun to play against on Deity.
Well, on the actual topic of playing him, the uniques, as mentioned, are both at the bottom tier. While the traits do have some merit to them, there's just no "wow" factor about Joao that would make me want to play him or go back to him once I've played him. And since we're disagreeing here, I can't really agree on him being "the most flexible" as I could name pretty much any situation where I'd prefer another leader over him. There's no need to make this into a topic about personal tastes on leaders; I'm merely suggesting that we all have our favorites and pariahs and that you can't really say there's a single best answer to a specific situation.
Heck, I used to hate to play as Burger King because I never got any use out of the Landsknecht nor the Pro trait (save for some late game drill~) but for a compulsive rexer, Imp and Rathaus are unbeatable; When you manage to Oracle CoL he's just candy and can't go bankrupt. As far as I know, people still consider him bottom tier.
For me the bottom tier is (in no specific order): Mao, Joao, Stalin, Saladin, SB which can all be summarized as having poor internal synergy save for SB whos traits/uniques are way too turtly for my liking and maybe Joao whos too expansion oriented with poor uniques. I don't like Hammurabi either, and that's also because of his uniques. He should make a switch with Gilgamesh next door and both nations would be better off
