I saw this on my first server. Epics were easy to get but we had global drops. The byproduct was that you would see a mob with a fantastic weapon model in his hand, then kill him and be disappointed.
Since then I've played down epics a lot. I just don't like the idea of them, but it ends up being easier for a developer or designer to just implement 16 weapon sets and call it a day.
You also run into the player issue. "Wut, no epic at lvl 10? /q lol"
(The above is very sarcastic, we all know those kinds of folks don't actually use commas.)
As I've added more recently I try to give it a role, or something special that might make it appealing to one kind of player, regardless of class, but not appealing to another.
Here's an example of that:
http://dungeoncrawl.us.to/eq/ak/item.php?id=133458
Some folks won't touch a 2h with a delay that high, others are put off by the negative regen. In practice, with the high proc rate, it's exciting to play with because if you're not in combat all the time, you're dying. You have to swap the weapon out to rest, which can be annoying and impractical, so there's a tradeoff.
Other examples are weapons with really low base DPS, but a fast and reasonably reliable proc, elemental damage, etc.
I'm a big fan of Borderlands 1 and 2, and while it doesn't translate perfectly, you see a very functional mechanic at work. The weapons are about more than bullet damage and rate of fire, they do special things, have significant advantages and significant disadvantages. You can find something that fits your play style rather than being funneled into an expected play style.