There are probably near as many discrete goodies in the 4e PH as there were in 3.5. There were a /lot/ of spells, granted, but comparing feats, class abilities and spells to feats, features and powers, and summing them up, 4e is not that far behind. And, the more balanced all-classes-use-the-same-progression design means adding more classes won't be as risky as it used to be. It'll be laborious, considering that each class has something like 80 powers (and for some reason - copyright? trademark? marketing? - they must all have unique names, even if they're mechanically identical), but it won't run the same risk of creating an overpowered (or sucky) class.
What does seem to be limitting, though, is that those choices are much more chanellized by class. You choose a class, right away, 7/8th of those choices go away. You choose a build, and almost half of the remainder become less desireable. Similary, with feats, between class, race, and level, many feats are taken off the table before you even look at them.
You really can't cover as many concepts with just the classes in the 4e PH as you could in 3e - not nearly. What WotC - and your DM - can do, though, is add more classes that /can/ cover more concepts, and do it without breaking the game the way adding feats, spells, and classes to 3.5 tended to do. Because all those powers are chanellized into specific builds, there's less opportunity for the unintended synergies of broken combos. In a way, it's a win-win solution. Those that wanted better class balance got it, and WotC gets to sell more suplements to people who want to play something other than the 16 or so 'builds' in the PH.
