The guy was a jerk and will die a jerk(I hope you'r happy).
Flavored coffees are a must so find a good source of coffee syrups. And yes, you can purchase Starbucks prepackaged and would be a big time saver for you. Always offer mild, strong and extra strong(shot of espresso added), too weak or bitter are the greatest sins. Make certain to carry Splenda and keep your granulated sugar in pouring dispensers and not little packets. Have on hand heavy cream(my preference), half-n-half, milk(ew), and a nondairy such as Coffee-mate.
When considering flavors, observe a 7-Eleven coffee center or a large gas-food stop. Hazelnut is one of the most popular.
To offer a tabsp of rum or brandy at 50cents each would be a compelling option. You'd be surprised to learn that Mr. Koffee actually suffered from a hangover and needed a bit of "the hair of the dog that bit him".
Be absolutely clear on one fact, Coffee Shops are enjoying a phenomenal growth in popularity. So offer the finest and boast about it in all your advertisements. Also verbally offer it before and after the meal and hang graphics of coffee filled cups on the walls and in your menu. And for heavens sakes, KEEP THOSE CUPS FILLED AT NO EXTRA COST!!! Have someone walk around with a fresh pot, offering to top-off(topless would be good too)
No coffee connoisseur would touch decaf but you must carry it. Without the caffeine I wouldn't touch the crap. It's a legal drug that you sell, so yea, go for it !!!!!!!!!!!!!!!!!!
HAH,one other thingy, the size and type of cup & saucer, OMG it's soooo important. My most precious position is a diner style coffee cup my grandma used as long as I can remember. It's handle is worn from use and I feel her warmth whenever I use it. Do not use mugs(double ew). I use travel mugs but I hate them. Smaller is better than larger in the case of coffee serving size. It's a very hot beverage that cools rapidly(iced coffees are nice for summer) so a small cup filled repeatedly is the ticket and the added impression of superior service is invaluable.
All the best,