I like the idea of an ability that makes your avatars stronger, but I thought double perp cost is far too much. Maybe something like a reverse favor, the higher your skill, the bigger boost your avatar would get, the more perp+ it would cost. I think +3 perp for an avatar with higher attack, defence and magic attack would deffinatly be worth it. As it stands now, there is more perpetuation- available than nessasary.

I get a 1 tick Refresh with +2 head/feet, brigid subligar, level 80 staves and Marduk's body. I'm honestly not bothered about getting the +2 body because perp-4 is overkill and not nessasary to keep an avatar out without Refresh. Having some ability which makes the avatar stronger, and giving more use to perp- wouldn't be a bad thing imo.

As for making all the avatars individual, it'd be an interesting idea but I agree that it's nice to give people the choice of which avatar to use. Most Summoners only seem to use Garuda because of Preditor Claws, and with all the avatar: MAB that has been added in recent updates I think this is SE trying to level the playing field with all avatars by making their merit pacts equal strength, or making your faviourate the best if you choose rather than having it preset.