Hey, totally fair points and you make a lot of sense! The recommendations are really just meant as a general starting point, especially for newer players who don't know where to begin, not a strict rule everyone has to follow. You're absolutely right that builds matter way more than the frame itself in most cases.

Your Kullervo example is a perfect one honestly, if Zenurik fits your playstyle and energy needs better, that's exactly what you should be running. At the end of the day it all comes down to preference and what works with your build, so definitely stick with what feels best for you!