We live in America, Pictures are all that matter. Small tiny pics that you can't see are pointless. This industry is built around fantasy but most sites do very little to create interest in the provider. Check out my furniture site.
www.buynewbed.com it's all about pictures. So for a provider website I would have a gallery of pics at 120 DPI that are 800X400 landscape style. About 60% of people use laptops are that are 13.5 or smaller and you don't want them to have to scroll down to see the full pic. You also don't want small pics or huge pics that take too long to download. So optimizing the pictures is very important.
Also I would have more galleries that play into mens fantasies. So get some wigs and take pics with blonde, brunette and red hair.. If you really young use wigs that are bright colors. Do photos in sexy outfits and as many things you look hot in.
Most website pics are boring and don't make you have to see that provider. Also you can do videos that don't have to be porn but can be very sexy and again make whoever is watching go "Fuck I Have to See HER"
Make reviews easy to find.
All the other boring things like services, about you, calander, BS, BS, BS that guys don't care about. You don't really care about us and we don't really care about you. Its all about what is in if for me. Americans are all about ME, ME, ME. So put things on the site that makes the client feel like this provider is going to make ME happy and I have to see her because of what it is going to do for ME.
Also if you travel you could put a registry on your site letting clients know when you are going to visit there town. They pick there town and there email gets saved in a database that automatically emails all customers when your visting. That way when you travel you get a lot more customers and it makes your trip more profitable.
Anyway provider sites are exciting to me because you have the absolute easiest product to sell. Have fun building your site and keep it visual.