I'd focus on making the Xbox an accessory to peoples gaming PC. Xbox One game works on PC.
Instead of trying to divide and split a fanbase that doesn't want to be split, I would use Xbox on Windows as a opportunity to enhance the existing stores (Steam, Origin, Uplay) and the specter of windows gaming apps, Discord, Geforce gaming experience, fraps, and so on.
I'd work with the other store fronts to make a uni-login, where you can be enabled on your Origin, GoG Galaxy, Uplay, Steam and so on, and display various things. Trying to consolidate everything and make it easily integrated into windows.
And if then, that the UI is great, and it is easier to navigate through all the content stream of an xbox PC app like a giant RSS gaming feed, that also supports MMOs and online games, what you'd end up was an actually hub that enhanced your ability to navigate.
And if there also would be a propiertary software that would pull achievements from the different platforms to make up a shared tally gamerscore, that would just be even more swell.
Then I would actually not sigh and stress out over the idea of yet another platform, username and friends list and currency and all the bullshit that comes with it.
Microsoft as the worlds largest software developer and the operating system provider have this ability to streamline our existing gaming content hubs into one cohesive package. I'd cancel UWP. That thing sounds like a stick in the wheel. I don't need it to be more difficult.
The incentive is of course that more and more people are joining PC gaming, and PC gaming is the largest reason to buy a PC over a mac. I'm getting so tired of the gaming on mac bullshit. The Mac Cider Wrap clients for FFXIV and GW2 are pissing me off. I'm stick of the emulation, and Apples willingness to keep ignoring the gaming spectrum.
Microsoft should treat gamers better and see the monetary value in appeasing them on Windows, even if they dont get the benefits from Steam, Origin and so on.
But to put in their own store in a overcrowded established dominion. No.
If I was going to buy Quantum Break it would because they would have to make a non-intrusive means of delivering it without signing up for bullshit that just makes it harder to access a shared unified games library. With the Epic Games Launcher also recently having been added to the roster, and Amazon also cooking up their own store platform, I am getting violently agitated and annoyed at Microsoft over this. If on top of everything you also play a whole bunch of MMORPGs, then it is getting really f**king annoying. Stop making it more annoying Microsoft.
I'd focus on trying to set up promising small development studios with medium sized budgets and see how they could reimagine some of the classic franchises Microsoft has lying around. All the Rare I.Ps. Midtown Madness, Crimson Skies, Top Spin, MechAssault, Freelancer, Dungeon Siege, and so on. There is so much. Focus on smaller projects. Maybe not indie, but smaller. Try and see what new talented promising development studios can do. Get more good and smaller games out the door.
Even if its not AAA a new Mechassault or a new Jet Force Gemini would be very interesting. They'd also help upcoming smaller development studios. It would require MS to really scout for talented studios and make contracts that are a good compromise between risk and reward. If a small studio gets 5-10 million for a Midtown Madness, that is not a lot of money, but with Microsoft backing and the name recognition it could really do something positive.