Yeah, it's a pretty standard Siege Tower of Power - in fact it's pretty identical to the one a friend of mine is working on. It's a pretty competitive list, though you take a certain amount of risk in not having any melee power whatsoever (beyond the defender). Stealth has a real potential to make your day miserable (I don't think Siege's flare spell helps with Stealth).
3 Stormsmiths is about the cost of a Bokur, you might want to think about going that route. You already have plenty of stuff to kill unit leaders (Eiryss, GMCA) and enemy solos; the Bokur gives you a really credible melee threat. Or at least a bit of a speedbump. Right now anything that can close to melee range is going to chew up crucial parts of your army.