[Fire HD 6 and 7 General] bibikalka:
I got my Fire HD 7 8Gb on a crazy Black Friday sale for about $30 (stacked Amazon deals), but it sat in the box for 1/2 year until the root appeared. Now I want to describe how the device functions for those who would like to undertake the whole customization process after getting root:

GAPPS and Play Store work, and having the latest version of Google Play Services (GpS) is not that critical (7.0.99 that works is recent enough). In fact, some people choose to block GpS via a dummy install (Google Play Services Blocker discussed @ 4pda). If your latest favorite google app cannot really work without the latest GpS, install the prior working favorite gapp in /system/priv-app, and block the updates via creation of the corresponding dummy directory in /data/app (as discussed for GpS in other posts)

titanium backup works fine

/system partition can be cleaned up if space is needed, by uninstalling some Amazon apps which are large and harmless such as Weather or Kindle or Silk browser

voice Google Now search works, and one can use Google Launcher too (seems sluggish), all this is installed via Google Play Store

With Nova Launcher (good quick launcher!!!) and GAPPS, home screen widgets work (choose the 2nd settings provider line when the widget choice question pops up)

the 3 buttons at the bottom don't look like the classic Android, and what I miss most is the task manager (the right Android button), so I put a Task Killer on Desktop to kill all stuff at once Update: It looks like swiping up from home button brings up a quasi-task manager. It's also possible to add a task manager to the swipe up action for the "Apps" button in Nova launcher, so there is some control.

AOSP keyboard from Lollipop works fine (undug from here) :

http://www.mediafire.com/download/p...dCyanodroid+4.3+GApps+(Lollipop+Keyboard).zip

The trick is to copy a couple of *.so files to the /system/lib from this package, or otherwise it does not run

For other languages, I could not add them into AOSP keyboard, only into the Amazon one. AOSP settings pop up first, but then transfer me to Fire's settings menu. Anybody knows how to add languages specifically to AOSP ? I thought here about messing with settings apk, but not sure that would help. I also tried a Titanium restore from another device with multi-language AOSP, no go either. I don't know enough Android to be proficient here.

Various Start Up items can be blocked via many apps available out there, and this makes Fire HD quite fast (my reference point is a sluggish yet gorgeous looking Nook HD+ )

Also, the USB OTG thing works even in the unrooted device, and can help for Titanium back ups when rooted, I could even plug in a USB card reader, with a micro-SD in there. Invest a couple of bucks into an OTG cable, and a USB reader on ebay, this way you get a flash storage for the device

So, other than a few quirks (non-standard buttons, no Task killer, and no additional languages in AOSP keyboard), Fire HD is a very usable and fast Android device. If these items were somehow addressed, I am not even sure that I'd choose a custom ROM since the current one seems very stable

I am now thinking that if one were able to replace the 3 buttons with the standard Android ones, add Task Manager to the right button, and recompile Settings with additional options enabled, than the device will be 95% close to stock Android. So one would create a custom ROM from KitKat, and then pull out a few key files from it and put them on Fire HD in key places hopefully without bricking in the process.

If there are more thoughts, let's discuss!