Did the characters become too cartoonish. Of course there was Latka Gravas who was always silly, but then they added Reverend Jim, Tony Banta became dumber, Louie became meaner, and then they actually cast another character to add to the fray named Simka Gravas...a female version of Latka. Was it too much perhaps?

When it became the Latka & Simka (and Tony Clifton) Show, absolutely.

in the middle of season four right and i thought something was off and thanks to you now i know what the problem is, not only are they more cartoonish the soul of the show from season 1 2 and 3 are gone seems like they focused on just being cartoon funny i mean the episode about the guy afraid to walk out of his home could’ve been good but they way the writing was set up it was just wack to me

I was not a fan of Simka. By the 5th season you can tell that it was coming to a end and I think they knew. They started wrapping up characters stories. Jim bought the bar. Louie met the blind girl, elaine met the short bald guy and weren't tony and his girlfriend going to have a baby? I think Marilu said they pretty much knew they weren't coming back for a 6th season.