Sounds delicious!

My first thought, having grown up eating prosciutto and melon all the time, is that putting anything else on it is blasphemous... but Googling around, I guess the mint-balsamic combo is a well-known thing? Either way, just make sure you get the good stuff. Good prosciutto is sublime (which is why I can't imagine improving upon it!). My grandparents always insisted on prosciutto di Parma, with all the official stamps and designations and all that. Prosciutto di San Daniele is good, too, but Parma was always our standard.

Also, make sure you've got a good crusty bread on hand. Bread is an integral part of an Italian meal. If you don't have a (very) good bakery nearby, the best bread I've ever made at home also happens to be the easiest: Jim Lahey's No-Knead Bread. The linked measurements are by volume, but if you have a scale, use 430 grams flour (I prefer King Arthur AP flour in this recipe), 345 grams water, and 8 grams of salt (stick to the 1/4 tsp. yeast). And I don't really like using the suggested wheat bran or cornmeal—just dust with flour. Anyway, while the shape (a boule) is technically more French than Italian, this bread is so damn good that even the most strident purists would forgive you. Seriously, unless you have a world-class bakery at your disposal, just make this.

Finally, it's to everyone's taste, but your dessert course is screaming for some sambuca! (Skip the three coffee beans—no sense bringing your fancy menu down to the level of a kitschy red-checkered-tablecloth joint. :) Failing that, maybe do a little searching for other good digestifs. Sambuca was just always the thing I remember being on the table when I was a kid.