I don't think the decision is as simple as "I run it, or I sell out." Private companies hire CEOs fairly often.

If you could get a professional manager in to help run your company, you would still have control and could fire/replace him. Richard Branson does not run his 250 or so companies simultaneously - he uses professional managers. He pools risk but the firms remain private.

If you sell out, you lose control of your business. That can be a good or a bad thing. (But you can only really get out if you lose control of the business.)

As my dad tells me, "If you sell out, get out." It's wise advice.