In my experience, yes. But that’s a matter of personal taste, of course.
Anyway, my feeling is they weren’t really sure about the format in the first two or three seasons - additional characters dropping in and out somewhat randomly, that sort of thing. From season three or four it gets more consistant. Additional characters reappear more or less regular but in accordance with backstories and/or the general layout of the show. Other additional characters even develop into main characters, and that allows for adding more range and dimension to the whole show. But that’s just how I feel about it. I started to like it, so I watch it - without analyzing in detail why.
It might be a factor that I don’t watch it on TV but on DVD. I don’t have to suffer the commercials and I can watch either the original version or the dubbed one. (Next on the schedule is the last season of Fringe, starting next week.)
