The only part I will argue about from the OP is the old "if it ain't broke don't fix it" part. Now I love all the Halo games even Reach. If 343 or Bungie were to keep releasing the same game even if it's "perfect" it would get stale very quickly. My best example would be Pop music, You hear a new song and think it's the best song ever until you hear it everyday, multiple times a day, you usually end up being sick of hearing it even though the song has not changed at all. In my opinion a little change is a good thing. If you don't try something new, you will never truly progress.