From my understanding one of the benefits to ceramics/glazed terra cotta is that it stays clean, and that the color doesn't fade.
I don't have anything more to add than that unfortunately. Manufacturer's websites will probably be helpful, and if they're not you can probably just directly e-mail a manufacturer asking your questions.
Another place to look might be Sauerbruch and Hutton, since they like to use terra cotta.
I don't think I kept it that way in the end, but at one point in a school project I had walls that were part concrete and part terra cotta. The terra cotta's color was to be matched to the concrete, and over time the concrete would get dirty and the terra cotta wouldn't, acting as a register to compare the concrete staining against. The studio was about "weather" (not my decision lol). Later I changed it to a copper and concrete facade, with the same materials on the inside, with the contrast in weathering happening between the inside and outside.
But anyway. Yeah, I think there's a lot to like about terra cotta, and I think it should be used more.