Are you sure you even have a company? If you can't sell it and have the new owner run it independently, is it even a "company"?
As you have found out, it is a huge leap from being independent to being independent and growing your operation to something bigger than yourself. I've been there, and it's not easy.
Anyway, how much of a business background do you have? It's a very different level of skill and experience that you need as you go from making money to pay the bills to set up an operation with complex expenses and incomes, not to mention management and legal issues that pop up all around when you start to grow, hire people, sign more contracts, etc... So first, decide if you are up to it. It's a lot of trouble for some people, sometimes more than it's worth. Do you really enjoy managing people?
So decide that first...
If you still want to hire more people and grow you operation, realize that you will be doing a lot of management and very little coding. You will be running around putting out fires, answering client emails and phone calls, giving direction to your employees, tending to management stuff you may not like to do, and so on. If you are into technology as much as I am, you will very quickly miss the good old days of coding and keeping up to date on technologies.
Anyway, all those warnings aside. Let's say you still want to do this. Ok, well to generate a vision you need to give it a lot of thought, and you need to evaluate where you really are: Are you doing development for a niche market? If so, that's great, specialists are always in high demand. Do you want to continue to grow in that niche? What kind of operation would you like to have in 10 years? What would your life be like? these are very open ended questions and you may feel I don;t address your concerns, but you have not specified in any level of detail what you want, only that you are not happy where you are.
One last note: I'll repeat: You have to think how much you like management stuff. I come from a background very close to yours, except I did not start out on my own until after about 10 years' experience. You will be doing a ton of management stuff, so you better have a good taste for it, or a way to deal with it properly. If you screw up your corporate structure setup, or hire people without carefully-written contracts, or over-promise deliverables to clients because you need the work for your new employees, you will crash and burn quickly. There are many more ways to screw up if you make your operation bigger.