Guayusa is definitely more like a coffee buzz for me than yerba mate is. More of a straight caffeine buzz, but also it has it's own thing going on, with whatever else it is that's in there.
Before you brew it next time, obliterate the leaves a little in a coffee grinder/magic bullet type device. That will give you a stronger brew. I have shredded leaf and I still have to break it down further....to leaf bits/powder.
How are you brewing it by the way?
Another thing to mention is that guayusa is very low in tannins compared to yerba, coffee, green tea, etc... so it can be steeped for a longer time to bring out more of the flavor and strength.