^ Bloodbath is a side project, dunno if they count as a "band" or not, but they are quite good.
My vote goes to Opeth, and if you consider Meshuggah tech-death, they're up there, too.
As for Melodeath, In Flames was pretty good for a while, and Arch Enemy's Doomsday Machine and Wages of Sin are both fun albums. Insomnium is thoroughly meh.