1) You can't do it by modding. It is something that AI never does and is hard coded. I am surprised that you guys never noticed it before. I thought that you were flooding MM mail with these reports on AI that doesn't use about half of the diplomatic options even if they exist in their politics file.
2) My vote is 'no go' for Mechanoid. It is nearly useless for 1000 points and the people that really want to have RP before competitive game can change that themselves.
On the other hand, I have included 2 types of emp files for all my moded races. First type with the default roleplaying characteristics and the second with the settings for greater challenge playing with and without intel. You can try that approach as well.