Step 1: Deathwish and Etched Sigil don’t affect Hydra. If you let this be channeling will again be dominant and having a new set doesn’t change anything it will feel much the same.
Step 2: If needed (and I expect it is) sneak in a Source and maybe a weapon that can support this build. I presume the x10,625 damage multiplier of the items is already included in the damage expectations and if so removing them should be compensated.
Would like to somehow integrate Mirror Image in this set.
Now this set works a little different (due to the heads), but I’ll quote an older post I made for a new set (it and many other ideas are in the Wishlist 2.6.8 post from Davez).
Maybe some ideas can come from it.