[Snake]

1 or 2 round cooldown on Seiryuu's Hunter Wind also works better than changing a whole mechanic to make Youkai more silly. It's not like Bonder doesn't have skills that make Bonded Youkai perform some stunts like a spinning slash or whatever, and Punishing Winds still exists.

Also, I'd vouch for Summoner (Base Class) to get more skills like it, that make you take control of the Youkai's action and position them well for big number damage, by using your own Momentum. Youkai being autonomous (in a sense of damaging) is what makes Summoner so broken in terms of fighting against. It's your 7M, and the Youkai's 7M together for 14M of action economy vs a single enemy's 7M.

TLDR: Cooldowns on all Youkai spells will be a treat to consider. Summoner should get some skills that influence their Youkai, trade their Momentum for Youkai manipulation so after the nerf, Youkai is stops being seen as a 'second or third player in the party' but a 'part of a Summoner's playstyle and rotation', given these skills are worth being used, that is.