I don't think you will find multiple OSX user accounts viable/enjoyable. OSX puts a lot of important preferences (keyboard/mouse settings for example) within the user account, so you will end up having a nightmare keeping things in sync and sane. You won't be able to rely on a lot of important tools like dropbox or 1password easily. Just stick with 1 user. Use docker or virtualbox/vagrant for stuff you don't want to run as your OSX user.

Here are some of my tools and tips.

- homebrew is great - homebrew cask is helpful, too - 1password or similar - virtualbox can give you clean playgrounds and test environments that match your servers - boot2docker is handy for quickly starting and running services like databases without polluting your mac directly too much - I also get a lot of use out of vagrant but YMMV - I've lately started using project-specific instances of chrome (created with the chrome SSB script). This lets me keep lots of tabs separate and easily pause work and resume later - The chrome Tabs Outliner plugin is also really key

Here's my recent blog post with more details: http://peterlyons.com/problog/2015/02/osx-development-setup