Elan: Use his strengths. Illusions wouldn't work (though Roy wouldn't know that), and a dashing swordsman is merely runny against a deaf opponent. Instead, have Elan position himself wherever is most dramatically appropriate.

Belkar: Brilliant. Easily distracted berserker with all distractions torn away (sound and sight). Good way to get the best use out of the little monster.

I'm just curious, though, what role Roy is intending to play, besides maybe cleanup. It would be another pretty good mark of growth if he had no set role for himself - Roy has always seen himself as the one sane man and acts on the assumption that he can't really rely on his allies to follow the plan in any event. If he built this plan purely on faith of how his people will act, and gauged rightly, then he's matured greatly.