I don't know nearly as much about how to properly raise pork but I do know enough to be at least a little dangerous. And it's fun to find good stories, such as this one about the Flaherty family in Iowa.
Same as with raising beef cattle, breed, growing conditions, diet, and generally low-stress husbandry and proper slaughter can make a huge difference in taste and texture. Indeed, because of the way pigs digest their food (only one stomach vs. a cattle's four), the finishing diet can have an even stronger influence than with cattle.
Some key things to look for when buying pork.
- Outdoor raised.
- Appropriate breed/crossbreed for growing region.
- Pink meat. Sorry, pork is not the other white meat, that was engineered.
- All vegetarian diet. And no weird stuff e.g. human leftovers, garbage, cookies.
- Certified humane. Not a must but preferred. I prefer AWI standards (Animal Welfare Institute).
And talk to the farmer or brand folks and find out if anything special was added to the finishing diet. For instance, some of the world's most famous pork forages acorns in the forests in Spain.
Finally, give your farmer feedback, good and bad, so they can continue to improve.