The key here is to take the bull by the horns and, while being polite, being firm about what you expect and need.

1. You will have to take the initiative here and make specific requests to UA. Preferably at ORD. There is nobody at UA proactively looking for a better reroute or extending hotels. As a disrupted 1K, UA will almost certainly issue you further vouchers for hotels and meals. But, you will have to ask an agent for them.

2. Turning to the rebooking, you should do the research to determine alternatives. UA would likely rebook you onto DL services to the UP, but you would have to drive the last sector (unless there is local bus or other transport available).

You will need to also check your travel insurance, but at this point it might pay for new tickets allowing you to simply book DL.