Are you entirely satisfied with the way that Happy Days ended back in 1984?
By ending with Joanie and Chachi's wedding? I bring this up because I was watching this video that reviewed Joanie Loves Chachi, and the commentator, Rowdy C said that Happy Days focusing on Joanie and Chachi's relationship so heavily (especially in the post-Richie/Ron Howard years) became a detriment to the series.
https://vimeo.com/277183241
In other words, they were arguably, a clear-cut example of show executives not understanding the audience by shoe-horning their favorite characters. Rowdy C summed it up by saying that having Happy Days end with Joanie and Chachi's wedding was the "hill that they chose to die on".
In an alternate timeline, I wonder if "Welcome Home: Part 2", the episode where Richie leaves for Hollywood could've worked as a series finale. Instead in the actual context, it's merely to give some proper closure to Ron Howard's character, since he never really got a formal "goodbye" episode back in 1980.