for desserts I use the saucer that comes from a teacup. I can usually put my two treats on it and it works great. When I ate the SAD diet, I would use the salad plate from my dishes as my main entree plate. Now that I changed my lifestyle completely, the larger plate works.
I would say a pasta/soup/cereal bowl would hold about a cup of stuff so my bowls are actually 1 1/2 cups. Most servings of pasta are 1/2 to 3/4 cup. Cereal is usually 1/2 to 3/4 and soup I allow myself 1 cup.
Since I only drink water, i have no issues using a 32oz cup or large glass. When I want to get fancy, i use my wine glasses and fill with water.