It is possible to not wear 4 pc and also not have the mastery items from highmaul, just depends on your level of raiding in BRF. Personally, with the ilvl buff I am using chest/shoulders for tier and gloves from Oregorger, Iron Maidens Pants, and Blackhand helm, granted that is just my own choice. I was also lucky enough to get a mythic Blackhand helm from my cache so it actually was an overall upgrade from the mythic Kargath helm whereas the Heroic version of the BH helm is the same same (and slightly less Mastery), so again, just depends on personal preference.
I don't know, I have to agree that our 4-piece is less than enticing. It's simply a save me mana on something I'm doing anyway with EAA instead now I cast PoH twice instead of once. I actually found the 2-piece to be a bit annoying. Timing for penance is irritating and I often want to clip it. We get the stack of evang. regardless of clipping. With that said, our whole set is meh. I would simply argue that it would be nice to have something to look forward to like other classes.