I totally agree with the both of you. Blackout's and adds are our weaknesses. When doing H VH and I am on blackout with adds coming in, the only thing I can do is pop 5 min CD for Empower Rune Weap which can help gain some control back but with heavy hitting TG warriors, Frostfire Mages, and Ele Sham's,... its rough. The times when I am on blackout at the 6 seconds or so after the intial pull, I start to watch omen like a hawk. One thing especially for most frost tanks, is there are soo many shiny tank talents that I forget about dps/threat. Frost for me atleast is a real balancing act and that could be where my threat problems lay.
But I would have to say that just a small tweak or an ability thats spamable with maybe a 5 rune power cost that does nothing but gen threat would be nice. Even if its on GCD, its more help than a 40 RP FS. I dont know about the rest of yall, but I am not liking the fact that even while in combat, I seem to be losing rune power. This may be designed as such to not let us stack soo much RP for huge dumps, but I can drop a DnD and hit Horn of winter and look up and those 5 leftovers are gone. It would be helpfull that with some spells like FS that cost soo much RP that it not degrade while in combat.
Just my 2 cents.