EzGo 2016 S4 High Output - Basic questions

I'm new to the golf cart world, but have immersed myself in research over the past week. Finally pulled the trigger on buying one yesterday - so excuse my questions if they sound elementary.
Two questions :
1. Is this cart one that I could get the speed modified on and would love your opinion. Would not want to void the warranty but would like it to go a little faster.

2. Any recommendations on accessories or any bells and whistles that are beneficial. It's basically the standard model, but I am thinking I should add glove boxes and or a stereo.

Thanks in advance!