Bannan believes the club need fresh faces to bring out the best in the current players.
"The squad here is really good and for whatever reason it didn't happen for us last season," he told the Birmingham Mail. "But if new players come in it's good for the players who are here now because it keeps you on your toes and adds to the team and to the squad.
"It means you've got to fight for your place and I think that will be a big part of this season because if you get new faces in everyone tends to work harder to try to stay in the team. With a few new faces we could do well."