Go read Plaxor's files before being an ass. The ONLY fleet list that gives you the Firedagger is battlefleet Bakka, a specific fleet list in plaxors flawed lists.
AAF Imperial shotgunning is a bad tactic, and I have never used it. I don't even do it anymore with the orks, since taking torps on killkroozers/terrorships costs extra now, and since it's possible with the changes to orks, I run a gunboat heavy fleet. We haven't even played 1 v 1 in months.
Even without Lock on working for Nova Cannons I would still run with 2 dominator's because I love the ship, I even use it against Eldar, it's an awesome all comers cruiser. Also, The nova cannons force me to go straight at you, just AAF to get out of my forward arc, and force them to turn then they aren't locked on, and pretty much useless.
I am so sorry that your fleet has a weakness, and you fight the two fleets that make the most of the disadvantage you have, but you don't see ANY other chaos players complaining about their fleets. Even though you suggested it, we can just go back to using actual fleet lists so no one will ever take the Firedagger again (Which is the least of your concerns, every ship in Bakka has fast tracking turrets for free anyways)....even though I don't even think they did anything in that 3k game we took.