At least you need to remove 50-bnep.rules file because genwall is working with bnep and you don't need a bridge.
In principle genwall do not change system files and should work with stock firmware + kernel power.
However genwall is highly configurable thats why it is maybe not so easy.

For bluetooth you need to edit /etc/bluetooth/main.conf for activating the bluetooth network which you already did.

I don't know so much about the software mods of android devices. But I guess the hardware is not limiting.

My own experience with android device were very bad, because they not supporting features which I use everyday, so they were useless for me and working with them and get things running were very time consuming compared to a personal computer and all my former smartphones.

However maybe I am thinking to much that a smartphone or tablet should behave like a computer.
But nowadays this is definitely not the case. They are mainly made for people who don't have a clue about pc's.