I was totally the same. I thought it would feel 'fake' if we got married ahead of time and had a symbolic ceremony. After lots of research and hearing from other brides (mostly on here), it seems like the big day in Mexico is no less 'special' if you sign the paperwork ahead of time. We have decided to legally get married in Vancouver a few days before we go to Mexico. I want it low key as well. Both sets of parents will be there, along with an Uncle and Aunt (that my fiance is very close with) that cannot make it to Mexico. I don't want any 'mushy' stuff, no ring exchanging, just the legal paperwork. We will probably go for dinner afterwards. We will also arrange to sign something in Mexico during our ceremony.