Not to speak for Mason as I think he's still around on occasion but this build was released in 2012 with Vanilla Skyrim and before Dawnguard existed...so there is certainly some room for tweaks with the expansions and DLC as you're noting.  All builds are typically fluid and can be adjusted by the player to make it their own so if that makes sense to you with the new content, then go for it.

Bagged and tagged!

Those two perks you saved in Master Resto/Dest I put into Ebony Smithing. Stalhrim light armor looks amazing on an ice vampire. I know Elven armor was a major theme of the building but to each their own right? The extra boost of frost damage on the stalhrim axe is nice, plus adding Dragonborn Frost to my shouts fit nicely with "breath that could freeze a man's blood". I stayed away from the Dawnguard DLC, as I felt neither faction fit the roleplay. I am an ancient Volkihar, before the clan got too comfortable with posh nobility.