You can change your htaccess to reduce the amount of disk reads in half on the server when accessing a page.
Note that if you update wordpress or click the save button on Permalinks page, it will get removed. This is why I remove write permission on my htaccess file.
Your image sizes seem fine. But on the About Us page the first picture with the lady and the necklaces is a small picture 360x360 but is 230KB which doesn't need to be 230KB as others are smaller. That one took longer to load. Also the image of the girl on Designer Classics slowly loaded after everything was done. It is large 300KB. Check images to see what can be compressed but still look good enough. The home page images could probably be compressed more and still look acceptable.