Hello,
1) All the available optimization settings are located in Theme Options > Speed Optimization. We tested the mentioned pages and don’t have issues with the speed. I sent you the results in previous messages.
2) I see overlay just for a millisecond and that’s all https://gyazo.com/2d2a6e3aaba01852b9af11597c8a91ea Can’t check the order process because we don’t have details to fill the eCheck fields. If you have any test credentials provide them to check. It takes some time to add to the cart but it’s no very long delay https://gyazo.com/086683a20496824101aff91274d51a4f
3) Requests that you provided are not theme requests, check them by yourself, these requests are requests from additional plugins that you use and from WooCommerce. We can do nothing with this.
Regards