Eh, I like the idea but it needs some work. For one, the History bit, remember this is a new timeline, you gotta think up your own reason for their establishment/existence, be it a ab original character being the founder, or whatever. Emperor Palptine's sith identity is mostly left unknown to almost everyone in the galaxy, save for a select few. Also 20 ABY would be the incorrect time, it's actually 1 BBY and to note that the dating system for the rp is 20 A.F.(After Fall)

So, you're going to have to do some reworking to make your faction fit in the new setting.