My Wife and I stayed at the Warwick downtown Denver 8 or 9 times over the last 12 years because we liked our stay so much. The Warwick ( refurbished ) used to be one of the original Playboy clubs of the early 70's, if the walls could talk.
The 15 th floor features a rooftop pool open all year round and heated in winter, very nice. During our Christmas stays I would tip the doorman and asked if he could turn up the pool temperature during our stay. It was like a nice big hot tub.
Many times we got underground/valet parking at 1 cent per day. Not sure what $ you may find today regarding parking costs but it never hurts to ask.
The restaurant on site is very good.
Although there are many hotels downtown Denver we never looked into them since the Warwick was ideal for us.