Well, we're going to need more info, like what kinds/types of fish you are interested in, if you're looking into a single species/specimen setup or more of an overgrown community tank.
And then there's what you mean by planted aquarium. Do you mean lots of delicate stem plants and CO2 injection, or are you willing to be more flexible in your definition. I have a heavily planted tank that would probably survive most monsters, but it's all anubias tied to big pieces of bogwood, and not the feathery stem plants and red foliage of a planted tank you'd see in a magazine or anything.
So, what kinds of fish are you most interested in? large Catfish and most cichlids tend to be very not plant friendly. I've never owned one or even seen one in person, but osphomerus (Giant Gouramis) might work in a large planted tank. Black ghost knife fish look stunning in heavily planted tanks, though you have to be careful about choosing tankmates. Or if you're looking into a giant community, angels or discus would love a 100 gallon tank, and you could have all kinds of tetras, rasboras, corys, etc.