Just reading through this thread about all the different possible allergies to possible ingredients makes my head swim. Unless the bride, groom, or one of the close family members or bridal party have an allergy and you want to cater to that, I would not focus on that. And sorry, but I would not explicitly list every ingredient in every dish. No one does that, regardless of whether the meal they are serving is vegan or laden with meat or whatever.
I applaud kherbert who has learned how to live with her severe peanut allergy and has said repeatedly, including in this thread, that it is up to the person with the allergy to vet the foods they eat, not up to the host.
So I think you just set aside all the allergy concerns being discussed here. Giving people plenty of choices and a heads up by posting the menu in advance is really way more than most people do for a wedding reception. My son got married just over a year ago. Everyone got a small portion of two entrees which the bride & groom decided on, a couple sides and some appetizers which were passed around. If anyone wasn't happy with that, well, they just kept it to themselves.
Another wedding I went to, again, everyone got served pretty much the same thing. It was a buffet line with a minimum of choices. I didn't hear a single complaint. Everyone was there to celebrate the couple. The meal was, of course, part of the celebration, but not the main focus.
LadyL, don't fret too much over this.