Absolutely loved it! We crossed from Argentina at La Quiaca/Villazon, then to Tupiza, a jeep tour for a few days finishing at Uyuni, on to Sucre, took Spanish classes there for a week (which was incredibly inexpensive and helped a ton!), then La Paz, Lake Titicaca (Copacabana + Isla del Sol). Would love to get back there to explore more!
That's good to know!, I'd definitely recommend checking the east side of the country next time (it's like a different country altogether in terms of culture, landscapes and weather), mainly the Jesuit churches and Fort Samaipata in Santa Cruz (where I live now).
If you happen to come back here I'd be glad to show you around town (Santa Cruz de la Sierra) and grab a coffee or something like that.