I think we are very far away from the SB overhaul that DMM got few months ago.
But you are absolutely correct - with the new SB mechanic a SB stacking team like that is absolutely insane. 300% Solar Blast plus all the additional damage from the skills.
I`ve seen a short video someone made to show it off. If setup as Team 1 they can nuke even the most crazy bosses (the time limited Godaibana duo boss) for massive amount of HP, and then they still get to attack with regular 6* stat line and skill damage.