The value isn't terrible for Barbashev, but I can't see the Blues taking a more expensive middle-6 player in return.

Kapanen wont make more than Barbashev

His cap hit was $3.2m on his last deal. While the structure meant that he had a particularly low QO, I doubt that arbitration is going to be giving him ~$2m. Seravelli seems to think it will be in the $3m-$3.5m range if they can't get something worked out before arbitration.