Show went downhill IMO when it kept recycle material from Season 1.
For example the profit painter gimmick. It was okay the first season. But then the next season or whatever it was rehashed several times. I remember there being a season with the
Prof X cop
guy getting it which was so nonsensical to me.
Also I felt like some characters didn't really evolve beyond season 1 and the drama it brung. Then there was the problem that characters didn't really stay dead because cheesy shenanigans somehow brought the actor back.
Side note, I just got finished watching the series about 2 years ago. I didn't realize how fucking annoying Peter was until rewatching the series.