Imo for premading you're not going to need blazing speed as you'll be at maximum range from the opposing team's rdps anyways, blink will be enough to get out of range from surges.
Either pom for pom poly on heals, pom arcane blast for dps burst or ice flows, but again you shouldn't need to really cast on the run (no mdps to kite, you should be within about 30 yards of efc anyways who has low mobility so he shouldn't range you in pushing for efc)
EFCs don't usually die until 10 stacks and are pushed back into their GY (or the entire team collapses on them)blazing sped or icyfloes on pushs in midfights it gives the mage more utilityz because the enemys are running away so u often have to position urself where they wont range u in ur 1cast, blazing speed nova the mass n if u have 4stak just big dick everywhere, icyflowz pushing for ffb on healers or juicy killtargs, pom is kinda useless besides the ooOoooOOOOOOoo more dmg or insta pom on a healer that shouldnt be in range of a pom anyways