I speak from experience - you can leverage the cooperation of 3-4 successful consultants to fill gaps or land larger projects, but you'll make more money consulting than you ever will trying to make your process scale.

The only exception is if you target a repeatable market for business processes.

Why does this have to be? If you pay the good consultants what they are worth, and then pass on the cost of them + an appropriate cost for leading the project(s) + your consulting fee for working within the project, you should make more than consulting alone, no?