Sooner or later it will be big changes in NK, and then the money and trade flows will be in charge, not the Juche priests. This https://en.wikipedia.org/wiki/Gravity_model_of_trade will be a big factor.
A rough calculation: To increase the standard of NK to a suitable level about $100 000 is needed per capita for the next decade = about 25 M x $100k = $2,500 billion. With > 15 % profit margin that is more than $250 bn in profit. This is a conservative figure.
If I were to give advice to the Norks I would say; “Make sure that you have good relations with Tokyo and Washington otherwise you will be swallowed by Seoul and Beijing. Perhaps you as well need US forces and bases for protection.”
... ask Vietnam.