Jailbreaking once allowed a lot of major things, for adventurous risk takers.
Jailbreaking now allows a few minor things, and the risks have passed beyond mere adventure. Not worth it.
Disable security? No thanks.
I don't think streaming is for me, but I do like the new Music app. I'd say it's 5 steps forward, 1 step back, and the inevitable revisions/evolution will make it terrific.
Meanwhile, I'll enjoy a little ad-free streaming radio to discover music. But when the free trial is up, I'm OK going back to the ad-supported radio.
30 days is long enough to break the pen sensor by inserting the pen without looking. Long enough to fail to find your favorite apps, but find the pre-installed 3rd-party junk just fine. Long enough to find the Samsung-not-really-cooperating-with-Google UI hodgepodge to be substandard. Long enough to tell that the awesome-looking curved screen edges are impractical and annoying. And long enough to read about the latest malware/spyware attack on Android, if not suffer an...
Keyboard as accessory--sure. It makes sense for some. Probably left to 3rd parties.
Detachable 2-in-1? No.
That will make sense in a far off future where iOS and OS X merge. Until then, it's still a useful niche for some, but not a niche I expect Apple to target