I'm in an odd position, possibly unique among remaining CN players. I signed up in 2006 and have gone through multiple nations. My longest break from CN was nearly two years, and I've had breaks of that length at least twice. If there's anyone who has gone away (for as long as I have) and come back as many times as I have, I'm unaware of them.
Anyway, I left for the first time (and stopped donating to the game) owing to rampant, unchecked cheating. That was a decade ago. Every now and then I come back to see if the lights are still on, sell some tech to people I know....
From my perspective, if you want to fix CN, you're going to need a time machine.
Not sure how to fit that into a questionnaire.