I used Windows (business), OS X (iOS dev), and Linux (backend dev) side-by-side -- sharing a mouse with Synergy -- for about a year.

As a regular user, I'd choose Windows, hands down. As a developer (or long-time Linux user, like you), I'd choose Linux. Ubuntu is the only OS I run now.

I recently installed Yosemite on my 2013 MBP, hoping it had fixed some of my complaints about previous versions. It was, instead, as massive regression. Many others have pointed out the same.

Stick with Linux. If you're productive and happy, why consider anything else?

The unfortunate thing is that non-Apple hardware is lacking in some ways, but you can shop around a bit and find something close.