2), 3) We can do nothing with the Revolution slider speed. All the possible speed options of our theme were enabled/disabled in Theme Options > Speed Optimization.
Our tests show a little bit better performance than your https://prnt.sc/wjru2z https://tools.pingdom.com/#5db9ef02e8800000
You may also optimize images, for example slider image https://prnt.sc/wjrwvf and it will reduce the page size and increase the site speed.
