Miku doesn't actually care about any of that. All Miku cares about is Miku, so she made a world where she could be happy - that is, live in luxury and without fear of the Idaten.
She's just being edgy and pointing out that even if things are peaceful now, ultimately nothing lasts. And she's...
Goroshky is probably just on the spectrum, and doesn't know how to connect with people beyond his special interests - it explains why he was hypercompetent in some aspects of the game while ignoring whole other dimensions of it, his soloing focus despite demonstrably enjoying playing with...
According to Narou, appraisal and item inventory are the two most powerful skills ever, as judging by how much they show up as the cheat skill of choice in novel titles.
With narouslop being what it is, it's actually not atypical for adaptations to be much more polished works. See also Taida na Akujoku Kizoku ni Tensei Shita Ore.