You pretty much just summed up a lot of how we'd like to make sure Tech Diffusion works.
As for the leaders being more willing to cozy up with the tech leader, that may already be a definition in their personality profiles. It's not really a trait issue but a personality issue. Traits : Direct Game effects from personality habits and leadership methods; Personality : Guides the desires and decisions the leader will generally make.
There are a LOT of definitions on leaders to aide in their personality profile and I haven't gotten to fully go through all of it yet. I'm not sure but that could already be considered there and if not... yeah, might be a good eventual goal to make that a consideration. I can now work pretty well with diplomacy modifiers and will eventually get down and dirty with it to improve it from a lot of angles. I'll keep that in mind when that becomes the current project but that will be a long while yet.
Admittedly, we don't have anything yet to represent the frustration of citizens about falling behind their contemporary civilizations in knowledge (the 3rd world country citizen mentality) and its another area to consider and probably in tangent with an eventual full review of Revolution mechanisms as well. Again... a project for a day quite a ways off from now but a worthy one overall.
Some good thinking all around though!