Would it make sense to hire someone? When you run a solo person business getting over the mental hump about hiring someone is difficult. If rewards are great and things are stable (16 years is stable) what is preventing you from hiring someone to help with at least some aspect?
"The E-Myth Revisited" calls this working on your business as opposed to working in your business. Otherwise you don't own a business, you own a job.
I thought about hiring somebody five years ago, but the fact is my client has gone itself from a small/medium sized business to a corporate, from no IT staff to now thirty and they are working to replace the production systems I wrote the middle of this year. To be frank having that much responsibility as a one man business is quite scary. Also when I originally wrote the systems for them I had no clue it was going to get this busy and no clue I would be 24x7 support, also at 62 years old I really want to start winding down :-)