Well, I got a couple of suggestions for you ;
- Your are using way too many css files, which might slow down the site, and reduce the google page speed test.
- Please change your font.
- I hope you provide the ability to change the color systems cause the default colors are a little bit too dark.
Those are just basics. May you please provide a link to your source code so that we can check out if the main problem is there. I mean, you might be using the wrong files and wrong language constructs in your code.
You might also want to make sure that your theme meets the WordPress theme review requirements. The theme check plugin helps you do that.