1. i would remove set items or nerf them a lot. They are to powerful.
2. i would nerf legendary gear drop rate. 1 pice every 20-30 minutes of average game play would be good enough. There is nothing special about legendary gear if there does drop 5 of them every minute.
3. i would remove half of the torment levels. There is no point to have so many Torment levels, people skip half of them anyway. playing torment 6 then finding a set item and skipping right into torment 12 is just stupid game design.
4. i would make a cap on paragon level.