Every season, with the introduction of new items, sets, skill changes. It has allowed solo players to go higher and higher in the rift/grift ranking system. Season 2-3 saw bots cap out around 40 and 45 or so. Keystone requirement is still a bit annoying, but no longer requiring 2 keys for both rifts helps. As a LoN bombard sader I am easily averaging 150b/hr with no issues, and if I run him for an hour or so prior to buffer my keystones a bit he can be around 80b pool exp which bumps me up to around 180-200b/hr exp running grift 700s. Pretty good rolls on all my gear, Swiftmount with 300dmg base(10% CDR, 23% AD, 950 vita/str+). Every piece of gear has a rank 75-80 gem caldessans in it putting me over 20k str.