I love GitLab, made it a corporate standard accessible to every single employee. But the current problem space is already huge, and you are struggling to solve all of it properly.
Branching off into an entirely new dimension, like an IDE will be, will make it even harder for you to satisfy existing customers.
The article seems to assume tight coupling between tools as a prerequisite for seamless integration between them.
I am the maintainer of git-appraise, and its founding precept is that tools can be loosely coupled and still seamlessly integrate together. All they have to do is store their data in the git repository in a common format.
The result works well. For example, a commit can be built by both Travis and Jenkins, and other tools can show both results without caring which tools produced them.
The rest of the suggestions seemed reasonable, though.