I'm honestly not sure (haven't
actually played with Jomon in MP yet, most of my "wisdom" comes from playing Shinuyama and TC), but on paper both seem like great additions to a communion... until they run out of script, that is.
If you're fielding a large communion, once his scripting is over your Mediation monk could well get into his pixel head to cast Falling Frost or whatever over and over. The fatigue wipe seems neat for reverse communion purposes, but I'd probably give him a bow of some kind on top of the matrix and script him to cast Mediation x5, Shoot Whatevs. The teaching sign seems *extremely effing great* to stick a matrix on, even more so if it stacks with PotS (I don't know that it does, though).
As always, if you have any doubt whether this or that particular tactic works or not, the
Debug mod is your friend.