I'm not entirely sure if this would work (I'm not an min/max guru), but I would think that reach weapons would be very useful for the character tasked with being the anti-archer guy. Guisarme + spiked armor to maximize the chances of AoO from them using a bow in melee. You could go spiked chain for the same effect, but that costs a feat and you run the risk of the 'Ah well, it was the spiked chain, not the dwarf, everyone *knows* that spiked chains are broken.' reaction.

Using the Cleric as the backup is a good idea. It's not that you don't want the Cleric up-front-and-personal, it's that when something goes badly wrong you want the Cleric free to move in and do whatever needs to be done. Buffing, healing, that extra smackdown to drop an enemy, etc. The Cleric is your 'reserve', to use military terms. Since the Cleric is perfectly capable of holding his own in combat, and as a full spellcaster, and as the primary healer, it just makes sense to hold him back. Let everyone else get stuck in, see where a heavy-hitter/spellcaster would do the most good, and then send in the Cleric.

In RL combat, one of the the biggest factors is terrain. If you're in a Thunderdome kind of setup, *make* terrain. Have the spellcasters drop barriers and restrictions on the battlefields. Clouds, walls (especially Wind Walls versus archers), etc. The archers (and spellcasters) are only as good as their line of sight. If they can't snipe, their effectiveness is reduced. That gives your heavy melee guys a chance. Of course, on average you're going to be moving slower than the elves, if you can drop barriers that affect the elves, but your melee tanks are immune to, that's much better. Freedom of Movement, Hastes, that kind of stuff.

Oh, just as a note: It may not matter, but if the other side is relying on archers and the like, make sure that the rules of encumberance are being followed. The chances of an archer actually running out of arrows is relatively small, but unless they have an magical everful quiver of some kind there is always the chance.