At that weight I think you would be fine with a 100 gram rat but I have a few words of advice. Don't worry so much. Your snake is going to be fine with a 60 gram rat every 5 days if that's where you decide to stay too. Just because your snake had a good feeding response doesn't mean its being under fed. I also don't see a problem with feeding more than 1 rodent. Your snake is going to eat whats it wants to eat. I sometimes offer a second rodent and sometimes my 1500 gram BP will take one and sometimes she won't. Its not a big deal. Good luck.