Years ago my dad was on the board for the local cooperative burial association. The one thing he was most clear about was that if there is a burial, choose the cheapest vault available. There is no material benefit of the high-dollar ones over the very basic one, it's only to make those folks who think they always have to have the best of the best happy. 

I bought our burial plots some years ago and told my hubs about it later. A couple years ago, we finally went and had our stone done the way we thought we wanted it, and it's set now and we're happy with it.

As many other posters have said, a good funeral director is a gift from God. Hopefully there is someone like that in the community and you can rely on them. It sounds as though you and your wife are the decision makers, since no one else seems to want to step up. You have to do what you think is right, and then live with it. Be prepared to deal with grumpy siblings. They refuse to do anything to help now, chances are they will be the first to b^^^^ and complain after the fact. It is what it is. Do what you feel is right, and let the rest go in one ear and out the other.