I don't see a need to limit characters right now so no worries there but be cautious if you don't think you can handle that many characters then don't worry about them. As for councilors It's usually given to the oldest member or the member that had been there the longest at least at half-blood so If you want to be cabin leader go ahead (Obviously Athena's cabin is out of the running there) The roma side works a bit differently but I'll explain more when the time comes.