Well I don't really use custom rom anymore, unless it's something like OnePlus One with CM built in.
But coming from a Moto X users I'm excited to see a lot of it's features being brought into Android L, such as:
-Okay Google always listening
-Ambient Display, which is similar to concept to moto/active display
-Trusted Bluetooth
-NFC unlock (okay, this is actually something common, but the Moto X had the Moto Skip, now Android L can pair with any NFC tags for unlocking.
It probably devalued the exclusivity of the Moto X, but it's good because I have more phones to choose from. The only thing stock Android lack that I still want is Moto Assist.