Oh nimrod how I agree with you on this one
I said previously that alliances tech and other trade are part of Civ games and only Civ games its in 4x and strategy games in general. So most of those the purposed things seem silly. One thing that I agree is that one time trade bonus is not good. If you end up only building caravans and looking where to route them, well I see it as kinda devolution of game and as unfavorable increase in ammount of micromanagement.
Though I do not see no contact before embasy as the same. I see it as option to give more use to dimplomats and one mor place where to spend resources. Which all seems to be good. But as I said I do not want to see it in this game. Another note regarding new players, this will most likely bite them as they will be unable to appreaciate the diplomats and effort of establishing contact (otoh chat might make all of this moot...). Other than that I'd love try this setting, just not in this game/now.