If you use your personal website to showcase your other projects, if nothing else that is one more place to link to all of them. Then, for example, if you blog about what you are doing and learning, any time you get people to link to your site you are also increasing the link juice you are sending to your other projects. And of course there are also the more indirect benefits of building your personal brand / reputation / opportunities for networking and becoming a thought leader in your niche(s) / etc.
