Nothing stops you from writing your own to-your-specifications launcher or SMS client or email client atop the openly-licensed Android stack (and leverage having an actually useful, widely-supported phone). People might even use your GNU-gold-starred alternative if it's more than barely functional, though the track record of said gold-starred software with regards to UX doesn't fill me with optimism. But I do wish you luck.
I'm still using my google-sanctioned stock android, and I routinely use some sort of closed source software...
My point was more like: I'm using google-android now, out of convenience, but I stopped strictly seeing Android releases[1] as improvements (and thus I _might_ refrain to use KitKat... if I'll move to a google-less cyanogenmod or to Ubuntu or Jolla I still don't know)
Also, My intention was not to be rhetoric: I just found Stallman definitions of freedom useful in this context to understand what some people are complaining about
[1] as in "Android used on Nexus", compared to AOSP
The problem is not bundling in closed-source applications... the problem is removing (and thus stopping development) of the previously-default open source applications
Are Nova, Apex and Smart OSS? I looked at their web pages, but I don't see any link to the sources
basically: you still have freedom 0 (and possibly freedom 2, if you're willing to go against the EULA)... but, concerning freedom 1 and freedom 3, Android (as in AOSP) is stuck to something like version "4.*"