honestly melee are garbage on thok heroic 10m, they tend to spend half the time on the jailer or running away from thok, but if u get a ret pally atleast they have devo aura every 2 mins for a raid cd so that helps. if the feral has a boomy set, enhc has an ele set, or the frost dk has something else he can sub in like a diff toon altogether that'd help your comp down the boss way easier.
range can be hitting thok all the time, esp a hunter with widows venom for -25% healing when hes changing phases.
heres our kill from a week ago.
http://www.warcraftlogs.com/reports/...zb4r1#fight=39
for our comp we have 3 hunters 1 boomy 1 destro lock. 1 guard druid 1 prot pally 1 mw monk and 1 disc priest who goes on a restro druid when hes bored for lulz.
as u can see hunters tend to do the most dps or near it just because of their uninterrupted skills, and our boomy is up there too, maybe hes just really good idk.
id say when u gain enough dps u can do blue-> red and skip green cause poison can be iffy without proper dispels, but sometimes its fun to give healers something to do.