My 18yo niece recently flew TLC-OAK on Volaris and my father-in-law has flown with them OAK-TLC. Both were satisfied with their flights and commented on the ease of getting in/out of the Toluca airport.
Volaris runs a shuttle service from the Toluca airport to Santa Fe where you can jump on the Mexico City metro (subway) to get where you need to go. I don't know if I'd do this if I had a lot of luggage though.