The benefit to one larger vs multiple smaller prey is time and money. And some animals will not take multiples. Other than that, it doesn't matter, if they are eating, feed them what they'll eat. As far as mood, could be a day or two or who knows... One of my boas out of the blue one day decided she didn't like my husband shuffling papers in front of her cage. And struck at him repeatedly, hitting the glass, and putting her tooth through her lip.
I had to pull her lip off her tooth very carefully with an earring. She was still pissed at him the next day and struck at him some more, however she was fine with me. So who knows.
I would start with offering 2 mice per feeding, (one at a time). If she takes them, you can bump up quantity accordingly. Can you post a picture of her?