Your comments

To iterate on this, I believe the actual workflow to be more like this:
1) cloning of the offcial repo.
2) create new feature branch.

3) create a Fork on github to store your changes (for either backup or working from different machines).

4) Sync both local and fork with the new official repo changes.

5) Complete feature and push to Fork.

6) Create Pull Request from Fork to official repo.

7) Delete local feature branch, optionally, Fork feature branch, optionally delete entire Fork repo.

Simplified version 
1a) Clone official

2a) create feature branch

3a) complete feature.

4a) Create Pull Request for that feature (meaning automatically create a Fork, push to it, and create a PR). 
5a) Delete Fork once PR is merged.

Step 3 is not currently supported from within Smartgit, but it should be possible to do using the GitHub API. Allowing creation of forks (which would be automatically added as remotes) would greatly enhance the workflow.

Step 6 and 7 are also eh at this moment.

Step 4a would be incredible to have. 

I work on multiple open source projects, some of them have 40+ repos each. I don't want to have and maintain 40 forks, it would be easier to directly work with the official and only create a fork if you need to store personal changes or create a PR.