Many, if not all of the most-liked concepts, are definitely groundbreaking in their own right. There’s zero correlation; if anything it’s the reverse. I think what’s just happened here is that people have grown so accustomed to disagreeing with your topics that it has the chance to skew your perception of what makes a “good” post. At the end of the day it just comes down to what would most benefit UII as a whole, combined with how well the post was executed.
For example, 3 of the top all-time suggestion topics, with 50, 40, and 30 likes respectively: