So basically the only draw of a blackguard is something that a Cleric gets 2 levels sooner or can be gained from a Theme now?
It's weapon vs a NAD and you get your own damaging hit in. An off-turn damage ping (Firecrafter Theme) will even let you get another OA off on your own. The power is correctly priced as an E3. What theme are you refering to that would replicate this functionality on an encounter basis? The reason I use Devil's Pawn is because FSS+ Devil's Pawn effectively does what Hail of Steel would do, a full 14 levels earlier.
The hybrid blackguard|ardent is a flat and major loss.
Sure. I'm not going to pretend like I play Ardents, so I'm not going to dispute that in the least bit. I only noted that Blackguard|Warlord is not bad, because there's some interesting synergies there. The one thing I do want to note is that as far as optimizing leader novas go, generating a cascade of OAs is extremely valuable considering the free action attack limit, and is pretty much the next level of leadstriking that builds should be striving for. The OA-fest from Fortune Spurned Smite might lose to Forward-Thinking Cut + Extra PP in terms of attacks per encounter, but the fact that its focus-fire and with a less competitive action type gives it value to consider.