Urza and Mercedian Masques are not really a compareable blocks.
I play all kind of formats, and I must say that Urza, while giving us a full time overpowered cards, it also gave us good cards, cards like Duress, Powder Keg, Argothian Enchantress, and more.
I don't really hate Urza block anymore because I don't use any of it's major brokenness; I use the good cards.
Another point that everyone else failed to make is that not only the other cards are over shadowed by the broken ones, but the broken ones themselves are shadowing themselves. There are plenty of uses for Replenish, why do people not think of that? If you see a Replenish deck you must instantly think "T2 Replenish Deck", why not try to come up with something a little bit more creative? Same is with Academy Rector, Yawgmoth's Bargain, and a lot of other cards. There are plenty of cards that are good, but are only used partially, and the same way everytime. How about coming up with something unique with that Living Death buddy, instead of copying the original Death deck?
Each cards has a use, it maybe easy to find, and it maybe hard to find, but you will find it if you try. Nothing is like when you surprise your opponent with something unique...nothing...
"How come people don't like originality and uniquness in this world?
How come people always go-with-the-flow?
I don't know? Is it all about winning?
Yes or no, but no matter what, it will never be as good as if it was your idea." -DÛke