I like odin and alexander they are fun avatars to use but you hardly ever get to use them seeing as they use your 2hr up in one.
My idea is to add in a move for each of them that they will use if you don't have astral flow active. They will work exactly the same as they do if you use them now (summon them use their move takes all your mp linger for a second then leave) except instead of using perfect defense alexander could use gospel of the lost to heal the party and remove erasable debuffs make the amount healed and number of debuffs removed based on ur mp% and odin instead of zantetsuken could use a watered down version of geirrothr (mabe make it an effect similar to 5000 needles but the damage will be based on your mp% up 2 a maximum of 5k at 100% mp and like 100dmg at 1% rather than 10k needles and stun + bind).
I just think it would be nice to see odin and alex out more often than just as a 2hr which in most situations really isnt as useful as the other astral flow pacts. and within abyssea smn really has more mp than it knows what to do with.