Another question. What's the best way to spread my dynasty short of conquering? None of my relatives have claims that can be pressed and no one seems to want to enter a matrinal marriage with my daughters. Will it be easier if I keep raising my dynasties prestige?
Yes, it get's (far) easier with more dynasty prestige - as a one county count with zero prestige marilinear marriages are a tough sell. However, you can always go for matrilineal marriages with someone second or third in line for a title. Either you wait for their kids to gain claims you can press, or you speed up the process via plots and assassinations.