my friends and i were discussing this IF there was a DLC that...so basically after they find the relics a few years later they decide to do even GREATER things than just finding the relics and defeating Umrail so they decide to recruit,build military outposts and have political support to expand to even new heights unlike my friends however I'm not crazy but just for laughs what do you think?

It would need a point or a main reason to do those things instead of just "why the hell not". They need something to oppose or support to justify themselves.

also by the time of Elder Scrolls Skyrim they have expanded to the four corners of Tamriel making them a powerful order and not to be messed with

....your going to love what my friends thought okay so basically they support the Empire plain and simple however when you walk in the the "headquarters" the knight leaders were arguing that "why should we support the Empire while they abandon us, and also the stamp out Talos" and two of them are wood elf and khajit and they also oppose this because the empire "supposedly" abandon them and the Head Knight told them to leave and take a moment to breath and we will "discuss it later"