Blizzard, Fire and Thunder are naturally already THM abilities, and Frost is a BLM Job ability, and thus this would not be possible because under the Armoury System abilities are not natively shared between separate classes and Jobs - you have to learn them on their default class and then crossclass them manually (and Job spells/abilities cannot be crossclassed at all). So this alone would not be possible I'm afraid.
Phalanx was actually a weaponskill in FFXIV 1.0 for GLA not an ability or spell like it was in FFXI - in fact, it was completely different to it's FFXI form in that it was a sword-based counterattack that became available if you blocked an attack with a shield. So I wouldn't be surprised if SE are keeping this in reserve for GLA/PLD for the future.
