After "trying out" Android for a bit, I have to say that I probably wouldn't buy another Microsoft Mobile, unless everything seems to work out. Better, if not more. Funnily enough, on my Android, I have only 2 apps that currently aren't available on WM.
In my experience, I have learned that I probably wouldn't be opposed to using my fav book app on Edge (it's great there, but sucks on ie on 8.1), but the fact that I have to use the lousy Kindle app that is still not updated, sucks. I can't even use the Cloud Reader because it doesn't recognize edge or even ie on wp 8.1. Not having certain apps for me is a major downfall. I'm starting to go off on a tanget, but basically, I wouldn't be opposed to using an alternative (i.e. pin it to the start screen) if said alternative worked for every single one of my apps that are important to me. Unfortunately, that method doesn't work for every app so eh.
However, if the Kindle app is actually updated, MLB At Bat returns and stays there, and some other apps actually create an app for WM and maintain it, I wouldn't mind returning. In short, basically what tgp said, lol.
I still use a WP just as a music player and that has been really nice, especially since TuneIn and iHeartRadio finally decided to update their apps. That combined with Metrotube, makes it great.