>>46884858B2/W2 are pretty tough, I'd say start with something easier for you first Nuzlocke, it's surprising how you have to alter the way you think and react. Give them a shot if you feel like it but don't be discouraged if you get whooped, and you can always just continue it as a normal playthrough if you wipe completely.
Just before E4, let's see how this goes, my team is pretty overpowered but whatever.