These are the builds i use on varian most of the time.

With the twinblade builds you can adjust talents depending on opponents.
All lvl 1 talents can work perfectly fine, so both lvl 10 talents. If against enemies with shields like , you might go for shattering throw in lvl 13.

The only problem I really can find with the Colussus smash builds is that they have terrible wave clear, but otherwise you can easely oneshot any squishy hero with it.