I do this fairly often as well. I keep a running journal of blends in my rotation, and after smoking half a tin or so, if a blend is just not a standout, or is “too much” in some way, I shift it to my blending list. Here’s a few combos that have turned out well for me: (I name them too - just to exercise my creative whim!)
Old LaGoblin- equal parts Pease LaGonda & Peterson Old Dublin
Bayou Hound- 60% C&D Bayou Night & 40% Pinkerton Era Granger. (This one really surprised me!)
Yale Dropout- 50% C&D Yale Mixure + 25% Dunhill the Aperitf + 25% Pease Samarra
I’m currently toying with blending Ashton Consummate Gentlemen with something... maybe some Sutliff Balkan II or some old Hearth & Home Namaste’
I’ve had more wins than losers, but I’m pretty picky about what gets blended. My “leftover” bin mixtures have been more passable than pleasurable.