[Q] Xperia SL from stock to beast :) topic

Hi,

I'm new and quite a newbie with android so, please bare with me :)
I will try to write a comprehensive guide on this during the process.

My device is XperiaSL LT26ii / Android 4.1.2 / Kernel 6.2.B.1.96 (stock, or default kernel) Routed with bootloader locked. Busybox installed.
So the only thing I'v done after buying is rooting it.

- How to fully-backup / recovery if anything goes wrong
Before doing any operation with it I wanted to backup everything (applications, ROM, System, documents) , and I hear that there is CWM or Xrecovery for that (mentioned in some guides), nandroid, but I found different applications on Playstore and don't know which one is the right one for my device.
I understand that backing up and restoring each of these system parts requries order and probably different applications,
Can we specify here which app should I use and how it's done?

- ROM and Kernel without unlocking possibly
http://forum.xda-developers.com/show....php?t=2593806 it looks like possible but considering that now there is cm-11 out and not yet for "nozomi" http://download.cyanogenmod.org/?device=nozomi , I would like to try any stable, fast , light ROM out there which works for my device. Preferibly with possibility to remove any google app ;).
If not, how can I unlock the bootloader and do the rest?
I saw also http://forum.xda-developers.com/show....php?t=1617219 which looks a nice kernel.
So , what's the most adaptive ROM / kernel for my phone and how to install / flash them?

- Getting back the applications
Once it's done, how to restore back applications and data? / with what tool, without loosing anything.