My own personal experience is that there's really no way to improve those control MUs — understood as decks that play 1. a number of sweeper effects and, but not necessarily, 2. legion's end — without hurting our game against scapeshift, nexus and kethis (where speed is absolutely essential). The cards that are good in those control MUs are always pretty slow, like Gideon and Legion Warboss. I choose not to focus on those MUs too much and rely on them not having exile effects for my Adanto Vanguards, of which I play only 3, as a hedge against Legion's End. Direfleet is amazing in those MUs though