Know Mexico City extremely well. Condesa and Roma are good areas to stay. Close enough to everything, safe, and lots of places to eat and drink.
In terms of things to do and see, I'd recommend.
A day around the Historic Centre (zocalo, cathedral) and the attractions around Parque Alameda (Bellas Artes, Post Office Building etc). Always enjoy a breakfast at El Cardenal if in the historic centre. Azul Historic, or Limosneros for Dinner.
Day pottering around Coyoacan. Lovely neighbourhood and you can visit Frida Kahlo's house. Neighbouring San Angel is lovely as well, and if you go on a Saturday you have the "Bazar Sabado" market.
Chapultepec Castle, Park and the Anthropology Museum which borders Condesa. Could even nip up to Polanco which is the high end shopping bit (although a bit soulless for me), I like the Soumaya and Jumex museums there.
Teotihuacan definitely worth the day trip, as is Xochimilco, bring some food, drink and go on the colourful trajineras.
As someone mentioned above, Lucha Libre is incredibly fun to visit. I'd recommend Arena Mexico for the CMLL show, just be a bit wary of your surroundings as it's in a slightly dodgy area, albeit full of people, just head back East towards Cuauhtemoc Avenue once done. If any interest in football obviously the Azteca Stadium is iconic and you could do a tour/watch a game as it's a club stadium too (even though my family are all fans of the main city rival so i'd get in trouble for saying that).
Food and Drink is incredibly hard to recommend without knowing what you're looking for. Street Food is mostly great, the high end restaurants are mostly great and in between is mostly great. The things I never miss are tacos el pastor at "El Vilsito", the aforementioned Breakfast/Brunch at El Cardenal, and a "Torta de Chilaquil" from La Esquina de Chilaquiles in Condesa. If you are specifically wanting restaurant recs for Roma and Condesa, then "Contramar" is an obvious choice, it's full of Instagram posers these days but it's still great, booking way in advance essential. I also really enjoyed "Meroma" on our last visit too, and have had good high end experiences at Maximo Bistrot and Em.
There is a big speakeasy cocktail scene in D.F. currently as well with loads of good options around Condesa/Roma/Juarez.
It's a bloody fantastic city.