I will jump on what @Guvnor said, Heimdall is not good in the wing.
Just faced him in the wing on two raids now in what should have been beastly teams. His talent is wasted on the wing. MN yes, Alby sure.
Why?
Their revive percentage is much higher than Heimdall’s. By the time he fires most or all of his team is dead, if he doesn’t revive anyone then he is dead too. Flank or better at tank for Heimdall.
He is CRAZY good at tank, even if he dies after firing the wings are almost certainly at over 100% health and the flanks probably are too (at least one of them). With that legacy the board still has to be good for you to win.