I think there was a brief time during the early X-Factor era where he was approaching Hulk level strength, and I believe his intellect went down, correspondingly.
Let the flames destroy all but that which is pure and true!
X-Men: Gold. More like X-Men: Bored.
I think it depends on you as an individual as to when the problems with Beast started. As with his ENTIRE cast barring maybe Cyclops, Morrison's Beast was on point, but if you're a 90's stan you obviously aren't going to like it because he wasn't an ape anymore.
"We come into this world alone and we leave the same way. The time we spent in between - time spent alive, sharing, learning together... is all that makes life worth living." - Jean Grey
I don't think you need to be a Cyclops fan to recognize that Beast's actions since AvX have been mind-blowingly stupid.
What really grates is that practically everyone and their grandmother time travels in the MU. Back and forth constantly, messing with this or that; especially the X-men. But somehow Beast actions are much worse than anyone elses. How many displaced time travelers are currently living in the present time MU apart from the 05? Dozens! Yet only Beast gets called out. Has the Watcher ever showed up to bitch out Kang for messing with time, I think not.