I guess it's all a matter of opinion because San Angel Inn is our favorite EPCOT Restaurant. Yes, it is dark, but IMO, that only adds to the romantic atmosphere. The closeness of the tables never really bothered me, maybe because due to the dimness of the restaurant I never really noticed it. They have the best frozen margarita I've ever tasted and DH and my sister both raved about the queso appetizer (I don't care for queso, so I can't say one way or the other). We've never had a bad meal there and although the menu isn't that of a typical mexican restuaurant, I think you can get tacos and such - I remember my sister had some sort of combination plate with a taco and maybe quesadillas that she enjoyed. The main negative would be the 'bathroom tables' mentioned by other posters. I remember when that used to be the waiting area and for that purpose, it was fine, but I'd politely ask for another table if they tried to seat us there.
kim