I like Sven but if he gets one more concussion he's done. It's a bad idea to put your hopes on what he can be when it's one little pop and he's gone forever.
But you shouldn't base what you do with a player with what might happen. Any player can have a career or season ending injury. Send Ericsson down and if Baer gets injured call him up or someone else who has been impressing in the Ahl.