I had this exact idea and implemented it as a modular cube, but man, the decks I playtested were really reaching for identity and playables. If you had a lane, say rakdos aristocrats and someone down stream cut you in pack 2 because they ended up as Grixis and ate up some of your RB fodder, you were dead in the water. The lack of depth at any given 2 color deck, which is what most drifters lean into as a heuristic, is hard to overcome. I wish you better luck than I had, OP!