Victim said:You don't think that encounters with mixed groups of enemies are more interesting than homogenous groups in 3e?
Well, not necessarily, no. See, I think it quickly becomes quite boring if *every* encounter has one or more Controller, one or more Artillery, one or more Brute, one or more Skirmisher, a host of Minions, and so on. And it's not just that -- your character's role more or less determines which monster you're supposed to attack (e.g. rangers keep peppering arrows at the Artillery and Controllers, while fighters and paladins are supposed to always tangle with Brutes and Minions). So while the first few adventures it might seem cool and awesome to take on a host of monsters in each fight, but soon it may become wearisome to always concentrate on certain enemy "types" in the spirit of team play, because you're are *expected* and even *required* to.
Not to mention that if you're not a tactically-minded DM, encounter/monster design in 4E might take a lot longer than it did in 3E.