With 25 medium langs out of 40 and the hive very active, I would add my first super to encourage the workers to stay (not swarm) since they will now have more room.
As for the queen cells, the workers will be waiting for their new queen but it does not mean the first queen will be excepted. If she is (~90% chance she will be) she will go to her sisters (other queen cells) and kill them. I hope you have drowns so the new queen can be mated. On very rare occasions, there might be two queens in the same hive before mating but this is OK as it will ensure only the strongest queen will survive after mating. -Mike