Switching foods/how much food intake is normal?

Every morning when I wake up I make sure to refresh Annabelle's food and water. I know she drinks well because I always hear her at her water bottle during the night, but I'm sort of worried about her food intake. She is currently on the mix I received from the breeder, which contains a blend of about six different Purina varieties, a Wellness brand food, and a Blue Buffalo brand food. The problem is that she doesn't seem to be eating very much of it - I would say maybe 10-20 kibbles a night? I'm sure that every hedgehog is different, but I'm just wondering if this is within the normal range of food consumption. I took her to the vet for a check-up last Thursday and she weighed in at about 280g.

Also, I am interested in changing her food. Her breeder feeds Purina due to concerns about fatty liver disease, but my experience with owning dogs and cats has taught me that Purina is junk, and I am hesitant to continue feeding it to her. My problem is making the actual switch over. I know to do it gradually, but I'm worried that if she's possibly a picky eater, and rejects the bag of expensive food I bought then I'm screwed, which sucks when you're a college student on a rather tight budget.

Ugh, I'm so confused right now! Any help/guidance would be appreciated. I just wanna do the right thing for little Annabelle - I try to keep my body fueled with the best possible foods, so it makes no sense to give my pet food with junky fillers.