Yes, it has been some time, but here are some pointers that have been repeated and apparently still need to be.
1) You do not need DW for fighting Arrae. Ever.
2) Giving **** to your caster for not carrying Wail of the Banshee is beyond foolish. Let me elaborate. Given that Wail is useless in Epic and mediocre at best in Shavarath, many good casters won't be carrying this spell. Enjoy my squelch list though.
3) Advertising for DPS and not accepting rogues - again, not going to work. I understand many newer rogues are too squishy to survive. But so are many new palis, rangers, fighters, and yes even barbarians. Myddo is your friend. Class discrimination is just going to guarantee I don't join your LFM at all - whether it is on my rogue (who can easily main-tank horoth on hard) or on my clerics/bards.
4) If you need more than fire/FoM to fight arrae, you might want to reconsider your gear choices.
And finally, a general rule of thumb for everything. Err towards shutting up first. Even if you *know* everyone out there is dumber than you, even dumb folks might just have that one scrap of knowledge you need to reach enlightenment. Peace.