I was just reading through this thread and I've got a couple things to add.
Charcoal is not useless, I have driftwood in both my tanks, and I run charcoal in my filters to remove the tannins. My water is crystal clear, whereas without the charcoal it would be the color of tea.
Once you hit your peak in nitrites, make sure to keep testing nitrate as well. When nitrate levels get too high it can stall out your cycle. I would do a PWC if nitrate hits 40ppm just to be safe.
just about any aquarium fish will adjust to any ph level (within reason). my water is quite hard and i have live plants, tetras (cardinal, black neon, glowlight, and ember), otos, and a pitbull pleco. everyone is thriving.
my advice is to stop testing your ph. wait until your cycle is completely over, then do a final ph test, and leave it at that. there are a couple natural ways to change your ph, but for the most part it is unnecessary.