I dunno. Just finished reading a post bitching about the right turn signal control being on the right side of the handle bars instead of L&R on the left like metrics. That's always something to discuss...
I've got an 09 RKC and an 09 Ultra and both of them are superb bikes so far (knocking on wood). The combination of the two I've got over 5000 miles since February. These are my first Harleys so I have nothing to compare to other than my ricers from the past.
People will always complain about something. Based on the number of discussions about the M8 sumping, I don't know if the bikes are getting any better or if social media creates more discussions. A dealer tech and close friend once told me his favorite bike is anything with an Evo.
Dang that question required some serious thought, because it is hard to answer with out writing a paperback book. To make a long story short, I did not get tired of complaining, but after Harley Davidson and I got through making the wrong things right, I ran out of things to complain about. As far as, "are the newer ones any better " I cant say cause I love my 07 RKC so much that I Have not even test rode another bike.