DL's contract is simply to get you from origin to destination including the official stopovers on your ticket. No compensation is required, nor will it help to ask for compensation. However, if the delay was DL's fault (for example, a mechanical delay rather than weather or ATC), DL will probably toss a small number of miles at each passenger as a customer service gesture.

Your OP sounds like DL did provide a hotel room, which is more than they are required to do.