Could you consider installing SpringSource Tool Suite as a package, rather than a folder? This will enable me to simply select "Applications" then SprintSource to launch, it rather than navigating several folders.
I can place it in the Dock, however, there are times when STS is relaunched and I end up with two icons on the dock (especially when STS relaunches itself). See the attached screenshot. Not sure if placing STS in a OS X package solves that.