Slow loading of all spirit sites

Hi there friends of Wpmudev. First of all, Spirit and Upfront are great to work with/on.. best tools you can have (thumbs up). But.. why does every page i make in this "style" - load slow, compared to many other WP sites? It looks like the Upfront i slowing things down a lot. Does someone have a great idea how to "speed things up"? (Of course i have also try to use it without any plugins). I need a good idea to make my Upfront sites faster in frontend. Please respond, i am pulling out all of my hair