I think you have much better chance long term and you can probably scale up if you want to do so. With the anchor client you are stuck in a very comfortable place but you can't raise rates, you can't do different things or hire people.
And worse, even as a consultant, you have a sample size of 1 with which to base all of your decisions re: what customers want, what solutions are best, etc.
Which makes you even less appealing to other clients.
