La Condesa and Roma are probably the two most gringo friendly areas, stay there. There's tons to do there, could do 4-5 days just in those neighbourhoods easily, 10+ days easy if you throw in the bosque next to it.. Mexico City al pastor hits different than anywhere else I've had al pastor. Mexico City is an elite elite food city, it's all incredible. Just use google maps/reviews, but mexicans aren't like us where any decent local spot gets an auto 5 and any place with lower than a 4.5 overall score is red flagged for being meh or worse. Anything from 4-4.5 is excellent in Mexico, anything over 4.5 is generally otherwordly. Don't overthink it.