If you need more flexibility, try the Residences.

We were on a 23hour layover last may, and I had 2 rooms booked. We were upgraded to 2 bedroom suites each. Our flights were at 11:30 pm , and they allowed us 8:00 pm checkout at no charge.

At that time there was no access to exec lounge at the Hilton, ( may have changed) but we were allowed to use all the Hilton facilities, pool etc , and we're given the full breakfast buffet in the restaurant. The Residences are just across the street.

They were very helpful and welcoming.