Generally...... if you bonk, you just rode too hard a pace for the distance you were going. Were you trying to keep up with others? 60 mile ride for me will be four 24 oz bottles maybe five, with about 150 Calories of carb mix in each. Six if really hot.
When I'm just riding for myself or with a couple others, that is usually all I take. Maybe a small box of raisins or a granola bar. If this was an organized ride, I'd have some oranges or bananas at some of the stops. Maybe try some of the unique things that the rest stops like to offer. Seems like they get in competition with the other rest stops on the routes and really come up with some interesting things. Though this year looks like that may not happen. Even the ride for May postponed till October is iffy.