I tried it and couldn't get it to work.
I couldn't raise my relationship with the AI high enough to even get a cease fire, let alone a peace treaty. This is important as the relationship requirements are 2-way now and without the ability to raise relationships on the Envoy I was basically dead in the water from a diplomatic standpoint.
Now... I could raise the AI's relationship with me plenty high enough by completing missions or donating resources, but that doesn't affect the reverse relationship points needed.
I'll admit I didn't do much testing with nonpreset teams. I've never had to use envoys to get a ceasefire so I assumed others wouldn't either... . However if that assumption is incorrect than yes I will need to do something about that.
That said, if the AI's relationship was the problem, then wouldn't you be needing the AI to send you envoys, not vice versa?
GoaFan, you may consider buffing those 3 tiers of diplomatic techs some more...IIRC I think you buffed the selfRelationshipBonus a little but maybe giving it a substantial boost will help (like, something on the order of a total bonus of 5 instead of 2)....
That would be the most elegant way to fix it. However I'm a little worried that it may make getting ceasefires with all the AI player to easy. I need to double check this but I don't think we can mod the negative relationship modifiers for diplomatic actions anymore.
Probably the last balance change I would make would be to change the Advent's Domina so that it's repair ability actually auto-casts. Or even better (since it is a higher level research than the TEC or Vasari support cruiser repair abilities), I would either give it an area of effect cast like some of the capital ship repair abilities or make it a passive always on ability that doesn't cost antimatter and slowly and continuously repairs every ship in range. The ability in its current form requires excessive micromanagement and it too high of a research level compared to the other races.
Well that really falls more under Seleuceia's balance mod a bit more than mine. This is more focused on reworking the mechanics of noncombat elements. That said, I have been meaning to raid his mod for the ability changes, as he's taken a few ideas from this mod, so there is a good chance you'll that in the future.
Other than that the only other thing I would like to see is for you to merge your mod with one of the planet mods that are out there (with the mod maker's permission, of course).
I was taking with AxelDude about that actually, he's released several really good planet textures to the community and sounds like he intends to release his own mod eventually. If that doesn't work out then at the least I should be able to make a version of Sins Plus that works with this.
I regularly pursue a diplomatic line with at least one or two AIs and although I believe your mod has made doing so slightly more cohesive, I would concur that in order for a diplomatic victory to be worthwhile over a military one in most cases, you could stand to go a bit further with it.
Are you talking about the actual diplomatic victory condition or making Diplomacy just as worthwhile as pursuing as military? I'm hesitant to do much with the diplomatic victory has its supposed to be completely overhauled in Rebellion, and I'm not sure I could do much with it if I wanted to. As for the later yes, this is just the first step. The big thing with the embassies was to allow players to pursue diplomacy without reducing their fleet sizes, which to me was the big issue with the Vanilla diplomacy. If that was successful then I can move on to the more subtle issues.