1. I would say that for the sake of simplicity, we can do one of two things: either we can designate a specific location where recharging can happen (which would require you to tell us a little bit about what makes that cave so special so that we can figure out something lore friendly), or Nightshade's aesthetic changes also came with the ability to convert food calories into charge. Which would work best for you?

2. 7 feet sounds reasonable! Enough to make them notably taller than most of their neighbors without it being outrageous lmao.