My raid group asked me about my first impression and I would like to share them.

Stance Dance
The stance penalty only occurs for WAR and PLD. I don't see the reason behind this. You get punished for being active and managing your role/job.
Tanks are rarity, this takes the fun to even play them. I don't feel like I get rewarded for using my tool kit.
This needs to be removed.

Onslaught
This ability is actually pretty good (and looks cool). It generates so much enmity it feels like I just did a BB combo. Dmg is mediocre (100 potency), yet reasonable for 15 sec CD.
But there is a reason I hesitate to use it, and that is its IB cost. I have to use a full BB/SE combo to refresh those 20 rage and it messes up the zerk/3-4 FC window.
Other classes (like DRK and MNK) get this ability on 30 sec CD/200 potency FOR FREE!
The IB cost has to go. Not 10, not 5, but NO COST!
Bind its inceased enmity bonus to Defiance to compensate and encourage MTing.