Ourph- The problem with your examples is that they're still incredibly narrow.
Damage bonuses from your warlord? That's an idea, except that Warlords almost never grant damage bonuses in that way, AND the damage bonus in question would have to be enough to outstrip the damage PENALTY that you accepted by using Sure Strike.
And killing a minion? I know that killing minions is the new thing, but I think people get too hung up on it. Not only would I not pick an at will power just to have something around that it slightly better at killing minions, but I'd also probably pick Cleave if killing off minions was a big concern for me. Plus, needing to kill a minion RIGHT NOW is not the sort of thing that happens frequently.