Carbs are great and shouldn't be demonised. It's all about what type of carbs you have and being smart about them. Promote good sleep and sleep inducing hormones that help to relax you from serotonin, dopamine and melatonin.
Err, no you don't. Work to YOUR range. You can still load the muscle and create great intensity to your squats with parralel and under parallel squats. Just don't be an overload bar with weight douche about it!