I personally find KE a difficult program to pool in so you may not want to be stuck with miles there, unless you are willing to go all in. The inability to book one way partner flight makes it quite difficult as you can't mix different alliances out and back.

That said, it's my holding account for SkyTeam, but I travel a lot through Korea and can make a lot of use of them. But you may struggle to book DL to South America for example as you may not be able to find flights both ways.