questions re rooting my S5 SM-G900i

[pjama1]

I have an old and new S5 that I want to do a complete transfer of all apps and configuration in particualar, "Beepn'Go" which is no longer registerable and thus unusable but it is still usable on my old S5. I'm hoping to use Titanium backup which requires root access to transfer all of my existing config over like it's the same phone.

I've done some reading on this but have a few questions:

Does rooting the device or something in the process reset it back to factory defaults? This would suck if I wanted to back up my existing config with Tianium backup.

Does it still increase the knox version and thus void warranty. I was wanting to tranfer/save/backup all the config on my old phone, reset it, confirm that the issues are indeed hardware, then do a warranty call on it.

Can I unroot it and restore to factory defaults like nothing ever happened?

Is there any other glaringly obvious flaw in my plan or blazingly simple way to do this?

PS: I posted this earlier in general Q&A but reposting here as it's more on topic.
I should also add that both the old and new S5s are identical in versions of everything in "about device" and the android version is 6.0.1.
I've also looed at Helium backup which may be an option to rooting but I've yet to determine if I can "restore" from old to new device.