Most people have already said all the sensible things I was going to say by now, but re: cantelope, I read an interesting recipe the other day that had cantelope slices served with a kind of chilli/garlic/fresh herb relish as an entree - though heaven knows garlic and chilli isn't everyone's idea of romantic...

As far as drinks go, you could make up some interesting varieties of iced tea, or something like that...

If you want extra stuff, I know a lot of people have said this already, but you really cannot go wrong with some really nice bread and dip.

Good luck with it... such a sweet idea...