I think you answered your own question

If you're not ready to deal with the tech side of a server then better to act as an affiliate.
We have two dedicated servers (we also host only for clients and of course our own sites, although we did recently start hosting for members here at the forums too

) and let me tell you, if my darling husband and business partner didn't know what he was doing, well...let's just say there's no way I could handle it on my own.
Apache what? Mailserve huh? Dedicated IPs and SSLs and things I cannot even pronounce much less manage...
I commend you for expanding your services and finding ways to continue to grow your business...if it's really something you want to do you could always consider bringing someone into your team who does understand servers and hosting and the like and you could learn alot in the process to boot!
But yes - running a server takes a lot all on it's own and there's even more work involved when you introduce the 'client' variable
Good luck in your endeavor and keep us posted on what route you decide to take!