Hi Kevin,
In my view, it is better to keep things simple.
Do not add features, plugins, CDNs, etc unless you really need them. Don’t add tech on top of tech just because “you can”.
South Korea has one of the most robust Internet backbones in the world in a very small geographic footprint. More than likely, you don’t really need a CDN in South Korean for a forum-based web application hosted in South Korean with 99% of the users from Korea.