Wowzers. I wasn't ragging on you for liking the show because I do as well. I can admit though that it's just a really really bad show. I mean I got super addicted to the show and have seen every episode (excluding the newest season) but it's kinda like being addicted to cigarettes. They taste horrible and can be kind of okay when your drunk but for some reason you just keep coming back for more. It always seems like a great idea when you haven't had one in a while but then you smoke a whole pack (or power watch a whole season on netflix) and you feel like you just dramatically shortened your own life.
That's any long-running show. Even the ones that start out pretty good, if they end up popular enough to run a long time, by the last few seasons you end up hoping they just stay watchable until the end. HIMYM isn't a bad show, but it is past it's prime. In 2 years we'll be having this discussion about New Girl. In 3-4 years we'll be having this discussion about Brooklyn 9-9. The only reasons this discussion doesn't come up more about Parks & Rec is that not enough people watch and Amy Poehler is a national treasure.