1.The Ms effect is entirely dependant on which class you are going with in arena or bgs. The effect can be dispel'd and is useless if you have a real MS class like a warrior or hunter.
2. Cold snap for that 2nd IB or nova is very imba indeed but with a 8min CD? vs blastwaves 30sec CD imo it comes out ontop.
3. There is only one 39 bracket so he is playing against the best and the worst.
4. Im not hyping its aoe snare. Cone of cold costs too much mana to be used effectively and has crappy damage also if you cone someone and they dispel they'll still be in melee attack range but with blastwave there still going to be a few yards away having to use intercept etc to catch up with you and then you still have nova and blink left. Blastwave can be used to be avoid being hit like frost nova or offensively to stop casts so its a oh shit or nuke button. Its basically frost nova but with high damage and crit chance. Also if you rotate blink nova and blastwave you won't be needing a 2nd IB.
Yeah the MS can be dispelled, it can also be reapplied in an instant, if a priest wants to spam dispell on a 1 second cast to either remove MS or the snare, he can go for it, he'll oom far far quicker than the mage, also his team mate'll die due to being constantly snared and not being able to get upto the mage quick enough without taking dmg. Yeah, this is a situational thing to say, but so are most of the things you've said in your post. Also wars dont have MS.
Youre looking at Cold Snap for just the second iceblock? Yeah, Blastwave has a shorter CD, but it's merely a spell that gives off an effect that a good mage can pull off without a problem anyway...
CoC costs too much mana? Crappy damage? Dispels? (again with dispels?), Youre actually hyping the knockback as a reason Fire > Frost? lol, in arena, melee in your face for 1 second, you're snared anyway, Hstring/Crippling. in WSG, i dont really see how the tiny knockback will change a damn thing. And using it to avoid Frost Nova? What the hell lol...
Also if you rotate blink nova and blastwave you won't be needing a 2nd IB.
again with just thinking about IB, and btw, even if you do rotate those things as a Fire mage, youre still gonna get gibbed vs a decent team in arena.
Your reply is far too situational, and part nuts
for me to really come up with a decent reply. But 1 thing I can leave you with, if a WSG team wants to get a mage out of the story fast for whatever reason, i dont think running in for that amazing auto dispelled Blastwave is gonna do too much for your team, I for one would rather sit at the back IV + R1 Frostbolts, trying to CC everything I could, and please dont reply, "but then you'll do no dmg and not kill the FC"...
Oh yeah Blazing speed is so usefull vs hunters (your nightmare), with it you can get close to them pretty easy. Who needs 2x IB when you can sprint away and its not on cd!.
BSpeed won't give you a match vs. a hunter, To beat a hunter you need to hug them and blow instants, as casting allows for them to get the small range needed and slam an aim shot/arc/auto in your face. And for that playstyle, I'd take 2 Nova/Frostbite/Shatter/IV anyday