I totally think you should host websites for clients. In my book it gives you so much more control over how things function and are setup. And, your clients will love the fact that you are giving them personalized customer service instead of them having to talk with the endless machine trying to get an answer.
What you want to look for is a Reseller situation. This way you have a "master control panel" and then sub-panels for all of your clients. You get to setup all your accounts yourself, setup email, stats, etc... There is then no delay for you to get a new account running.
You also should charge for the service and make "residual money". It's a great way to create a flat cushion of money coming every month from your client base. I charge anywhere from $10 to $25 per month for the hosting of their website depending on what they need (i.e. how big the site is, special functions they'll need, etc...). This fee is only for hosting, I charge other fees for any web maintenance...
My current Reseller account is with MidPhase and I've been happy with their Tech Support. When something goes wrong the client will contact you, then you can either see if it's something you can fix in your own control panel (which is often the case) or contact your techs via the phone or email in a trouble ticket. The key is how fast your techs respond and how good they are...
Hope this helps!