Wasn't Albania under Hoxha awfully similar to the "European North Korea" you're after? Isolated, batshit crazy - and thankfully small enough to be ignored.
It was, but Albania had a fraction of the population, a fraction of the economy (including GDP per capita), and no friends, since they hated everyone from Tito's Yugoslavia to the Soviet Union to China. Resource-wise they didn't quite have what Romania did either.
If Romania went full juche state, Moldova would have been annexed in 1995.
I'm not really sure if they would or not. It would be a huge gamble, because it could end with regime change if they fail. If they win, then they've made good on their ultranationalism. Of course, a lot of Moldovans will definitely resist, and there would be a huge flow of refugees to Ukraine and beyond. Ukraine obviously doesn't want a border with an unpredictable, violent state like Romania and the refugee crisis that will result. Would Ukraine ask for Russian or NATO assistance in defending Moldova?
There's also the thing with Transnistria--would Romania annex that? Could they cut a deal with Ukraine to avoid a war if they give Transnistria to Ukraine?