We need help in Wordpress Performance

Our website is running tremendously slow and after trying recommendations from GT Metrix such as adding expires headers and changing plugins, adding image optimization plugins and performance plugins. STILL the site is crawling. We have asked for assistance from the hosting server and they say the problem is not on their side.

Cloud Flare was suggested at one point though we didn't apply that as of yet. We do have several hundreds of photos as we are an art organization. We have sized all photos for 700 pixels or less. We are using a five star wordpress theme that has been purchased thousands of times with very high approval.

We are not looking for somebody to tell us to the above solutions. That has been done and not succeeded

We need somebody who has above ordinary WordPress skills who can solve the problem

Desired Skills are HTML, PHP, WordPress, Web Services Development, Website Analytics