On to new matters:
I just noticed a similiarity between the protheans and the Krynn from the game Galactic Civlizations II. The Krynn were originally a multitude of different species having evolved on a single planet who devoted themselves to pursuing a religious/cultural dogma called "The Krynn" (meaning "The Way"). All who embraced this dogma would call themselves Krynn.
In the game, Krynn have huge cultural bonuses, meaning they influence other species very easily, drawing massive amount of tourists (economy) and immigrants (population). A good Krynn player (or a Krynn player left alone for the entirety of the game, which only happens once in a blue moon) can decimate every single enemy in the game without firing a single shot by simply exerting so much influence over the other players' species that their populations basically give up on their former identities to become Krynn.
Reminds me a little of how the Prothean Empire worked. Though less religion and more "Hey, you're strong and we'd like you to add your strength to ours. We got money, resources, loads of fine *****es. If you say no, we crush you and wipe your species from the face of the galaxy. Fair deal?"