Juvenille discus should be kept in super-clean water, and fed heavily.
Bare bottomed tanks are good for juvies as they are easiest to keep scrupulously clean. If you don't keep the water clean enough with juvies you are very unlikely to end up with fish which grow to their full adult size and colouration.
They become stunted easily, which is typically seen in its earliest stages when the eye looks bigger in proportion to the rest of the fish than it should do. If you look at the relative size of the eye of your discus in comparison to the rest of its head, then see if you're comfortable.
Another symptom is the shape of teh fish - perfectly round ones being the aim, they can become more pointy depending on diet, but genetics plays a larger role in this than it does with relative eye-size.
If you have the time to keep the tank clean enough to avoid stunting your fish with gravel, plants and wood in it, then fine.
I keep cardinals and a pair of rams with my discus, and they all get along fine.
I agree they aren't as hard as a lot of people say, but they do still demand clean water and good varied diet, particularly when they're juvenilles, to grow to a good size, develop a nice shape, and display good colouration in adulthood.