I love this mod and thanks for sorting it for the S5 Mini!
... but I now have got a Galaxy A3... and clearly it's slightly different! You can re-name the buttons, but not remove them. At the risk of being cheeky I've attached the SystemUI and Framework-res files here if you could have a look!?!
Also, on the A3, you cannot remove the brightness controls in settings (unlike the S5, S5 Mini) - so if there is anything you could do about that I would be very grateful!
Certainly a pint of beer in it for you - and much kudos!