User blog comment:Yapby/All Unreleased Contents (Units, Quests, Raids)/@comment-26567149-20150927233821/@comment-71.167.5.30-20150928230601

The thing about Avant is that he doesn't provide BB fill on Crit, and doesn't boost Crit Rate on his SBB. Griff also boosts fill rate on SBB, so you'll be getting some more efficiency out of Griff. He's also an Elemental changer. Avant does boost spark damage though, which can supplement his lack of a crit rate buff, but to make full use of his leader skill you'd need someone who can actually buff crit rates.

Same thing with Chrome. He may provide a bigger spark buff, but he lacks the boost to attack stat, which goes multiplicatively with sparks. Plus, Rhoa is an elemental changer, which is a big advantage, and gives Def ignore, which can be helpful in cases where a boss needs to be taken down a certain HP threshold quickly but activates a def buff. Chrome, however, offers more BB momentum.

Dolk also doesn't completely perform the same jobs as Krantz. Along with that, Krantz's LS is more offensively based than Dolk. Then Krantz can heal (though not that much), and is, again, an elemental changer. Dolk, on the other hand, buffs def. Krantz is also a more efficient mitigator thanks to his ES.

The new units aren't replacements. They're simply units who can do something that some of the older units can do, and have different secondary abilities. It's just a matter of preference here, as none of the new units are much stronger than the Griff's batch. They can just do things that Griff's batch can't, and Griff's batch does things that Avant's batch can't.