I run Devastating Blow in most of my decks, thank you very much. But nothing stops them from using Ascension and banishing Panic off the top and like anything, just because there's answers doesn't mean it isn't stupid. There aren't any good answers to forced passes/skips which Trunks has in spades. You're most likely not going to stop Trunks' Evo 3 picking up a Sword Slash and skipping your action. The timing of the Dev Blow is crucial which sometimes it just doesn't work out especially if Red Panic hits the discard because of the damage from Dev Blow for example. I'd run more discard hate if I could but some styles just don't have enough. There's also little you can do if they build up a good amount of Red Bribe and Red Relaxation.
I like Quick Blast, but in Ruthless it's tough to fit a set in. It's more freestyle cards which can screw up your game plan especially if they crit it off at the wrong time and as an attack it's obviously lousy.