Hops such as Citra and Horizon can impart a mango like smell. Very nice effect in certain beers when allowed to shine through. This beer worked pretty well on my grandma, not to mention everybody who tasted it: http://www.brewersfriend.com/homebrew/r ... xperiment- If you do use them, add them to the secondary like any fresh fruit.
Never brewed with it but i bought a 6r of craft beer from Hawaii that had passion fruit and i believe mango, definately not to my taste but interesting.
Could you lightly mash a soft fruit and add it to the mash (or steeping grains) like you would with pumpkin or squash? I've read about pectin set if you use too high temps wtih fruits, but that's much higher than what you'd do with grains, I think?
With fruits, the majority of the carbs are already sugar. Putting them in the mash will only create problems for the grain conversion, without any potential of benefits from the fruit addition. Yep, fruit beers tend to be harder to clear naturally because of the pectin, and additional tannins.