I'm gonna be that person who just can't answer directly :P
Are your people late or early ppl? DH and I eat at 6 every night and are in bed at 9 or 10. Even on the weekend we're in bed by 10 or 11. If your friends are a bunch of old fogies like us, make it early ;)
Whatever you do for desserts, I'd make them small and portable. Whenever I serve dessert (I'm always in charge for holidays and family gatherings), cakes and pies are the last to be touched. Small things, like toffee, cheesecake bites, tartlets, etc, are the first to go. I think that way your guests feel like they're being less of a piggy piggy than if they had to get a slice of everything, KWIM? lol You can also come around with a tray and offer seconds and people won't feel bad having "one little piece".
I'd do the rum cocktail. Rum cocktails can be made in advance; champagne cannot or it'll go flat.