We enjoy -
-pastries in Norway (the most popular seems to me the skool bread, but we preferred something I think was called the cloudberry horn, it seemed like a Norse version of a cannoli)
-kaki gori (snow cone) in Japan
-Anything from Karamell Kuche in Germany (OMG, if you hit it when they are making the popcorn fresh, get it), and also the apple streusel and the bratwurst with sauerkraut from Sommerfest
-any pastry from La Patisserie Boulangerie in France (we actually like the whole CS meal offered here, they have some good sandwiches, french bread pizzas, and you pick a fresh-made pastry for dessert)
-Tangierine Cafe in Morocco has an incredible Shawarma Platter (like gyro) that comes with a few sides. You can get chicken, lamb or a combo, and it is HUGE, enough to share between two for a light lunch or more for a nice snack, plus you can sample many things. It comes with Baklava for dessert, which in our experience isn't the best baklava we've ever had, but it's good.
-Fish & Chips from Yorkshire Fish Shoppe in UK. It's smaller than other CS credit meals available, but it's good.
Those are just the snacks and CS bites we like to nosh on. I got the impression you're not interested in table service?
I recommend at least 2 afternoon/evenings for World Showcase to appreciate the best it has to offer.
ETA: If you're interested in adult beverages, the margaritas at La Cava del Tequilla inside the Mexico pavilion are incredible!!! I don't know if they still sell margaritas at a stand outside, but skip them and go for the ones inside! I'm drooling just thinking about them!