That 100 SG price point might be more in line if the value of the items on the mission pass is not at the same level as ours. (I see far less cosmetics than the version we have)
As for the fact mission pass went over to JP, it was inevitable, I'd imagine NGS having a similar system as well. We were just a testing bed for it and since it went down so well and it raises people logging in daily for the missions to complete their passes of course Sega is going to treat it like a success and put it in more things.