Don’t feel so bad – there are lots of types of pizza and lots of variance in quantity of toppings.
As @ipsedixit (sort of) said, it’s more about whether your crust and your toppings are a match for each other. As in, a thin, neapolitan-style crust can barely hold up sauce and a bit of cheese before it collapses, whereas a New York-style crust is sturdy enough to support a whole layer of ziti (And then, of course, there’s a Chicago pie that you could load up with as much sausage as it will hold.)
Personally, I like enough topping that I get a some in every bite – I don’t want 1.5 pieces of pepperoni on a whole slice. But even distribution is key to not having a loaded center.
You might enjoy a look at these past pizza threads (with plenty of topping loading going on) or join in with your experiments on the current Dish of the Quarter thread, which happens to be on Pizza.
(And then, of course, there’s a Chicago pie that you could load up with as much sausage as it will hold.)
