I commuted at varying distances for many years. The longest was a 58 mile round trip, and I found that I did best if I did that only four rather than five days, taking the train or the car on Wednesday. This plus one decent ride at a weekend meant I was doing close to 300 miles per week. I was pretty fit.
25 miles each way is long enough for you to play around with it, do some of the journeys in Z1/z2, make one of them a tempo session, and so on. Great training.
My most recent commute was 16 miles each way, still a decent distance but I found I didn't need the rest day for that one.
As for nutrition, I'm with the big breakfast brigade.