My main question is how to prioritize diplomatic efforts in the early game, such as diplomatic research, bulding envoys, and doing missions in this expansion.  The game seems harder than before.

How to use the ability to offer missions to other players is not clear. Are the rewards set aside when the mission is offered?  If not, do you get a bad reputation all round if you can't deliver when the mission is done?  I tried it and wound up well hated and not clear why.

Thanks