When I look at the big picture I don't think it's Xposed anymore!
1. Stock android has massive amount of improvements, most of the forks/custom ROMs looks quite similar. Therefore there is smaller need for custom roms. Android maturity - stagnation problem. Also system partition security of marshmallow makes it harder to mod.
Root previously gave ad-blocking, firewall, xposed.
2. Marshmallow brought official App Ops.
3. Today we have free No-root firewall with hosts ad-blocker - Netguard (apk virtual vpn)
http://forum.xda-developers.com/android/apps-games/app-netguard-root-firewall-t3233012
https://github.com/M66B/NetGuard/releases
There is developement of build in vpn client for netguard too.
It's nice to have alternative software.
4.
Also people don't want to team up. Era of individualists.
Imagine how spectacular would be collaborative project of joined forces:
@niaboc79
@Wajk
@Wolfbreak
@Pandemic
@shoey63
@serajr
@NUT
@zxz0O0
@ondrejvaroscak
@nailyk
For example aosp/cm base with sony camera and few cherry picks or even something entirely else.