That is one extensive list but for the life of me I don't see how much of what you are talking about is something average smart phone buyers are clamoring to get hold of. In fact, no one I know even mentions those capability. They make calls, read mail, check weather, text their friends, play candy crush and look at FB. That is about it. They don't work for The Verge where they pretend their phones have to double as a desktop computer. These are average smart phone buyers.
You say you want that entire list to know you are up to par. Also something I don't completely believe but I'll take you at your word. Much of that I read in your list are in the "nice to have class" of features. But even for those OS that can do these things, I can bet a fraction of average phone users want any of it or know it even exists. Microsoft built in a good chunk of the things we requested in 8.1 and much of what they are doing at this stage of the game, IMHO, is under the hood for developers.
Microsoft is playing the long game like they always do. They don't build in features like blinking your eyes to change web pages, swiping your hand to move a web page and other gimmicky garbage Sammy did and for what? Showmanship. Nothing more. I know a few with those phones at work and I have never seen anyone use them. In the airports, waiting rooms, wherever I spot these Sammy devices, I have seen NO ONE using them. Its fluff.
Personally 8.1 update is a game changer. Cortana is off to a good start and will only get better as development fleshes out over time. Notification is also something I wanted in this OS. We got it Those core features are what people use. Facebook app written by Facebook is pure folly. Facebook can build or it can be built by another dev. Either way, you get a platform that can run a Facebook app. You should spend time in this ecosystem and not those others. I'll feel so much more complete that what you think about that greener grass you think you see.
FYI, this list doesn't contain what I wish to see in Windows Phone, my list for I wish to see is far, far larger than the one I wrote. What my list really was is just stating what was promised to come with WP8.1 and didn't make it. Some of them were already in the SDK even but got removed in the final version!
Frustration with this update for me was a two way thing:
1- Things that was leaked and promised to come with this update, and didn't make it.
2- Things that I wanted in this update, regardless of them known to be coming or not.
SO, my list was about the first thing. Not exactly everything I want in the update.
You know, when you are late to the part, and your OS is far back at no.3, an update shouldn't be about having only what others have, for Microsoft to succeed they need to have what others don't. This is not the case til now. I wanna see Microsoft succeed, I know they can do more, enough with catching up with the competition, it's time for us to lead.
You can say all you want about costumers not realizing that it can do this, or that, and believe me, I never ask for what's gimmicky and what doesn't work, I want things that matter, that a lot of users that use a mobile phone currently don't even realize they need them. 20 years ago no one knew they needed a smart phone, but now it's something that no one can live without. This is what I am talking about, maybe I'll start a thread about all the things I want to see in the next Windows Phone update, but I wouldn't know cause lots of people will attack me as we haven't got a hand on this update yet.
Anyways, I am glad that you are satisfied with what you have now, I think you shouldn't look for any update at that matter, if you're that satisfied and don't need anything else than what this offers, then maybe the wheel of development should stop now and have a rest.