Since portability is a high value here, why not use the type keyboard all the time? I've gone from the surface pro, sp2, sp3. In all cases, I always used the type keyboard and mouse track pad....
I love my WP experience, 1520. I still carry my iPhone 4s for the few apps I have to have (connects to wifi only). I don't see me going back to an iPhone.
You mention overcoming local storage limitations ... You can access your OneDrive files using a web browser, then it is not on your local device.
There is a windows phone Starbucks app. I've had it for more than a year. I have the 1520 phone. It is called Starbucks locator. It is a true Starbucks aoo, not a 3rd party app.
I've been on the 1520 for several months. Love it, even though it took several weeks to adjust to the win phone. I had an iPhone prior.