I suspect it was better when there was a weak between each season.
Side characters can't be too one note though. How I Met Your Mother gets ripped a lot for various reasons, but part of the reason the show is so great is largely due to their recurring side characters and how they are both memorable
and
sparsely used. Marshall's dad, Randy Wharmpess, Ranjit (admittedly whose bit gets stale like TC mentions but it's usually literally one line he says), Arthur Hobbes, Lilly's dad, James Stinson...
Not only are they great, but they're sparingly used and they're usually involved in differing story scenarios so we see them behaving differently (again with the exception of Ranjit), rather than someone like Cricket who is just a degenerate doing what the gang says, or Charlie fucking with the Waitress. They're slight variants of the same story.
https://i.imgur.com/cEQy3f4.png / https://i.imgur.com/gWKaLHC.png
https://i.imgur.com/u6JR7qX.jpeg