I actually think that Paladin represents more work than the monk. I base this primarily on the fact that paladin in 5e relies heavily on smites, and those require either a working reaction system or some alternative to a working reaction system.

So we will get paladins during the patch that tests the new reaction system, whatever that may be. I have no idea whether that will be patch 6.

Monks do have unique features that will need to be implemented, but there is a decent mod that adds them on nexus, so it can't be THAT hard to put them in the main game.