PCat, I can't think of the issue that had the dragon stuff. There were feats for Lingering Breath Weapon that let the bw do 1/2 damage the second round and add 1 to the rounds between breathing. I believe there was something in there as well for Breath Weapon Substitution that let the dragon use a different form of energy than usual. Can't remember anything else from there. Someone here (IIRC) suggested taking any metamagic feat and applying it to the breath weapon and then increasing rounds between breathing by the number of levels normally added to the spell level.
Large and in Charge is a great feat, but requires an attack of opportunity to use, so it's limited for a dragon...but awesome for a hydra. (Of course, you wouldn't want to do some kind of dragon/hydra/true ghoul hybrid...that would be Evil(TM))