Eden, Seat of the Sanctum Having a land that does something later in the game is a useful tool to mitigate flood, so I doubt Eden, Seat of the Sanctum is utterly unplayable
Thats an eternity in Commander, so I wouldnt expect Concierge to come back more than once per game, but that also means the other creatures youre suspending in limbo also become non-factors most of the time
Conjurers Closet is probably the best option for this
Instead of dealing with the players Commanders, try and work your way around the other cards that enhance the Commanders powers
And he's a great equipment tutor to get you anything you need
Theres a smattering of beefy boys to choose from, like the classic Verdant Force, but nothing comes even close to how powerful creatures have become in modern Magic