Funny question...now that it comes to it, and I never realized this, I'm not sure there are too many VAs I enjoy all that much that don't have a lil bit 'o this or a lil bit 'o that added in, whether it be perique, cavendish, burley, orientals, cigar leaf, or latakia.
I think Christmas Cheer, Dark Star, and BWF are straight VAs, and if so I enjoy all 3. In fact they were once my absolute favorites. Over time my taste for McClelland VAs have faded somewhat though. However, all three are still very good.
If I'm not too much mistaken, Best Brown Flake/ Kendal Plug is straight, and if so, that would be my favorite.
Were I to go with the best VA dominant blends however, Marlin Flake and HOTW would take center stage followed closely by VA Spice, Sweet and Savory, and Stonehaven.