Tips for backyard wedding/reception?

We are planning our wedding for October of next year on family property. It’s going to be small with around 50 people, with a short and sweet wedding and a reception to follow.

Here is my issues:

1. we are doing a potluck in a tent. We plan on having a generator out there for the music and lights, but any tips on keeping the food warm during the ceremony?

2. what do I do about bathrooms? It will be in a field with the closest house a few hundred yards away. Do I rent a porta potty, or shuttle people back and forth to the house?

3. the area is on the edge of a field under open trees. The direction the bride will be coming from is pretty open and I don’t want to be seen until the last minute when I start walking down the aisle. Tips and tricks on how to accomplish this?