1. Staple Breakfast food: Vietnamese-run doughnut parlors for sweet lovers, breakfast tacos for fans of a savory breakfast. Less common, but more delicious: diners that serve biscuits and gravy.
2. Good fruit, vegetable, and other produce markets: these probably exist, but you're more likely to go to a supermarket. Fiesta has an immense variety of international fruits and vegetables, which for me makes it at least the equal of some hippie farmers' market with only a few different things. Sometimes you need tomatillos. Tons of specialty markets in the city's many ethnic enclaves.
3. Non-chain fast food under 10 dollars: There are drive-through steak restaurants, but those don't meet the price requirement. There are plenty of places where you can get cheap Chinese or Mexican to go, but I don't know if that counts as fast food. I think I've seen some taquerias with drive-through as well.
4. Exceptional high end restaurants : Not so much, especially by Paris/New York standards.
5. Reliable mid-range food: This is probably the strongest category for Houston. You can get just about any kind of delicious food, in unhealthily large portions, for less than $20.
6. Good general supermarket : Houston has Whole Foods and Rice Epicurean markets, but Albertsons and H.E.B. are more the standard. Fiesta is good for international foods.
7. Good specialized bakeries for dessert: I don't think this is a particular strength of the city. You can get a decorated cake at just about any large supermarket, since most of them have bakeries inside. Stand-alone bakeries are more rare; most people just go to House of Pies.
8. Wide range of cuisine: You can get great Indian, Chinese, Vietnamese, Thai, Tex-Mex, and Southern food. I've been dissatisfied with the availability of non-chain Cajun food, and those seeking European cuisine may be disappointed.
Dylan, any additions?