Hello,
Revolution slider is plugin to create advanced sliders, it’s not for the basic e-commerce site. Quform is the plugin to create advanced forms. You can use either Contact form 7 or this one depending on the form types you need. It’s also an extended option, not the basic one.
Smart product viewer – this is a plugin to create 360-degree product preview, it’s an additional feature, not the basic one. The same for all the other plugins we mentioned. You can enable them but only if you really need them. There is no need to keep the plugin enabled just in case.
If you want to enable a lot of plugins then you need to contact your hosting provider after that to make sure that server response time is ok because I saw that if all the plugins were enabled then server response time was too slow.
Anyway, if you are not satisfied with the theme speed we are ready to give you refund https://themeforest.net/refund_requests/new
Regards