Cask Focused Breweries

In terms of cask beer, absolutely. Dry Dock doesn't really even do cask beer, although their SS Minnow Mild is godlike on normal CO2. Dry Dock is more of an American-style brewpub, while Pint's and Hogshead are focused on English cask beers.
Pint's is authentic almost to a fault. Because they don't do a ton of volume and their casks don't hold up more than a few days, there's a strong chance that some of your beers there will be old and rough. I'm not 100% sure, but I think all of their house beers are cask-only.
Hogshead is the better of the two, IMO. They're very technical and their beers are very, very tasty. I've never had a single off-note in anything they do. They do a 50/50 mix of CO2 vs. cask, so you have options. A lot of people know Prost in Denver, but Hogshead is kind of like their English brother. I'd legitimately put them in my top 3 breweries in Denver list.