The supporting cast has run their course....except.
Oleg, still hilarious and one of the best things on the show. I've never found Earl all that amusing, his I'm old, I've done drugs, I was born before the wheel was invented schtick got played out several seasons ago. Sophie hasn't been funny on a regular basis since Season 1 and Han is just kinda there to give the other characters someone to make fun of.
The waiter from Season 3/Luis had great promise but they just faded him out after a handful of episodes. Would have loved to see how his crush on Oleg played out.