Also...

Long time no see you, modernized Najin-class :3
There is talk on Namu that these new destroyers will replace the Najin class... but given North Korea's longstanding tradition, I believe the ship will likely remain in service, with new upgrades to squeeze every last ounce of power possible out of the design.
The ship's biggest weakness is that it's a 60s/70s design, not stealthy, and has outdated weapons (especially the larger naval guns; the one pictured was slightly upgraded in 2014 with new anti-ship missiles and autocannons). At the very least they could redesign the superstructure and other structures to give it some mild stealth - I've seen precedent for this. To go even further, maybe add some new radars and sensors. Maybe ditch the two manned 57mm turrets and replace them with... let's see, 324mm lightweight torpedo tubes? Upgrade AK-230 turrets with AK-630-like turrets and replace two 100mm manned turrets with new 76mm auto naval guns?