It is your dream day and you need to do what you and your FI want to do, not what other people want you to do. I am the first grandchild on the one side of family and everyone was shocked when I mentioned we were doing a DW rather then an at home ceremony and traditional reception. At first I thought maybe we had made the wrong decision, and I was tired of people telling me that we shouldnt be having a DW. We finally decided that its what we want, and what we were going to do. Like you, the only people I really truly cared were there is my immediate family, mom, dad, and two brothers, and Fi only cared if his mom, dad, brother, and sister in law were there. Turns out they were all for a DW (my older brother had a failed engagement and lost a lot of money planning a wedding at home, so my parents were all for it, and FI brother and sister in law were married in Mexico and his family thought it was a great idea). Anyone else that comes in my opinion is extra and we will be happy they are there. I think you truly need to do what you want to do so you have no regrets. And if you do have an AHR then all those people can come then if they cant make your DW!