Idea For Additional Raid Content

I realize that the team is hard at work on content for this game, but something that bothers me at this stage of the game is the lack of raid content. Two takedowns just isn’t enough in my opinion. I was thinking that something could help with this is the Proving Grounds. They already have a takedown like feel to them. My idea is, what if you could hand eridium over to the guardian at the entrance of each of the Proving Grounds to turn them into a raid version of that trial? Each of the bosses could have an Invincible form. This would add six more raid bosses to the game with minimal effort.