A5-A7 doesnt require the ENTIRE party to do all the mechanics.

A5 if you have at least 1 tank, one healer who are on the ball. Everyone else gets to ignore bomb mechanic.

The dPS if they fail when they get a marker on them and don't move away the tank can just take the boss to the other corner. boost happens its obvious because the entire party is running.

A7: as long as you stand in one spot behind most of the bosses you are accidentally helping share damage or avoiding bad things. The only part that requires entire party focus is the different elevations part. And atleast one mindful person to turn the water tornado into a ice burg.

A7 if the tank kites the boss out of boulders dPS can follow boss and dodge as well without much mental effort.

As long as you have 2 strong DPS knowing how to fight the heart and stun adds. Youre fine.

The last fight requires ATLEAST 7 our of 8 to be doing the mechanics. The other fights don't require this.