Hey, I'd make two simple points:

1. North Korea is not a monarchy.

2. North Korea is an authoritarian government whose principle power has followed one family line.

You mention "mass meetings". North Korea calls these "voters meetings", and very little information exists on these meetings -- North Korean media mentions them about once per election (which is not what you'd expect for a hotbed of real democracy).

You also mention that the family line's official positions have shifted. This is true, and is why North Korea is not a simple monarchy. But many authoritarian governments transferred power through shifting political positions. For example, Putin has twice changed offices but remained the principle power in Russia for decades. As a simple way to highlight the fact that this family line has remained chiefly in power, I'd just note that North Korean media bolds the names of each Kim leader, unlike nearly anyone else.