Personally not a fan of purple pig or girl and the goat. Foods solid but a lot of better options out there. What’s your definition of nice or really price point? Chicago's great because there are restaurants with great food at affordable prices as well as amazing food at not so affordable prices.
I do agree with an earlier post that if you want steak Bavette’s is great.
Blackbird, Avec, Publican, Proxi, Pacific Standard Time, Roister are all great options that are more reasonably priced
Boka, Kyoten, Next, Acadia, Parachute are some of my favorite upscale places
May be controversial but IMO the burger from Au Cheval is the best burger around (with bacon and fried egg). There’s a reason why even locals wait an hour+ for it.