The dumping of Aperture by Apple is one of the most disgraceful episodes in the slow demise of a once spirited company.
As a pro I set up myriads of clients with the application to sort vast libraries.
Now they, and myself have been totally dumped.
This from a corporation that has more wealth than many countries. Apple should have sold it off or maintained it for the pro market even if it ran at a loss. Loss of face is worse than loss of profits.
Capture One is the only other choice out there. Lightroom is clunky and PC UI'ified.
I would say change over asap ..Apple is now a company run by suits and spreadsheets. It has no soul left.
While I dont agree with the demise of Apple etc, I do think it was a bad choice to dump Aperture. I realize they need to focus on certain areas, and Aperture didnt fit within the current plan (i.e. it was not about money, it was about focus). But as you say, there were other ways of doing it - spinning it out, or incorporating aperture level tools into the new app, etc.
I often wonder if Aperture users had have mobilized and strongly reacted, whether Apple would have gone back on the decision. Needless to say, its too late now as many people have already made the shift to other software.
I have tried lightroom in the past, and again after the announcement, and I really dont like it. Aside from staying on Mavericks (or maybe El Capitan), I dont really have a plan.