Finder used to be a lot worse, with tabs and once you've got all the shortcuts down it's not too bad. Spring loaded folders are really handy. Some time around 10.10 they added a shortcut for showing invisible files, which is absolutely essential for any developer. If I had to pick one area to improve, besides the ds_store littering it'd be general network file system support, SMB has always been a second class citizen and even AFP is just slow.