When playing WoW Classic I've noticed that water bodies have improved graphics when compared to the original 2006 version. Also there is a lot of grass when playing on the highest settings (I don't remember seeing that much back in the day).
Are there any other in-game differences that weren't present in patch 1.12.1?
Note that I'm only interested in in-game changes like for example Class/NPC balancing, graphical improvements and quality of life improvements. I'm not interested networking, servers or addons.