To my understanding, there are pros and cons to inviting (well respected) researchers to co-author a paper.
Pros: Being a co-author with well-respected researchers puts one in a good light. They can make valuable contributions. You improve your chance of being invited to work on projects with them in future. All these points can advance one's academic career.
Cons: Too many cooks spoil the broth. There is more chance of conflicting idea and styles, which might lead to frustration and delayed publication. They might not contribute as much as you hoped. More authors means less credit for the work per author.
I would like to hear your views on this.