I think SkyDeli is dead. Most flights that used to serve SkyDeli now get nothing.
Fastbreak is on 1-hour flights, full beverage on longer flights. Snacks generally served at mealtime on flights over 3 hours or so, meanls generally over 4 hours.
There is some variation to meet competition. Delta will typically match what competitors on the same route offer.
The above is for coach. In first, there is a little more food, but not much.
"In God we trust, everyone else bring data"