1) If you're used to a retina macbook pro, you're doomed. There's nothing with as good display and touchpad.
2) If you can handle low resoltions (1920x1080 or even 1366x768) and generally lower quality screens, get a Thinkpad. New ones are very expensive but generally solid, while older ones are cheap and work well with Linux.
3) If you want a good screen, there's only Dell XPS 13. If you live in one of the few lucky countries, you can get it with preinstalled Dell Ubuntu fork.