Is there a recommended way to install lights in an apartment? I was thinking of one circuit for all rooms but wondering if there was a limit to the wire length in 14/2 due to voltage drop. Maybe some sort of radial pattern is better? there would be a total of 12 outlets in the ceiling. Question: if I install LED recessed lighting, is the limit still 12 per circuit or can you increase in this case?

I am going to rewire an apartment since we are opening up the floors to level them. This apartment is very old and at the time, someone decided to run all the NMD cable along the baseboards on the outside. I want to move everything to underneath the floor and through drilled holes in the floor joists. To do that I have a few questions; I have attached pictures of the current mess where the cables all go into the panel. (a) All the wire is NMD but of varying age, can I re-use this wire or should I repull new NMD cable manufactured during the current year? I don't think there is any difference in copper spec, it's just the sheathing that on 1 or 2 wires is looking brittle (orange and grey/black coated sheath) (not knob tube) (b) Is there a recommendation of number of amps per room (non kitchen, non bathroom), say bedrooms, lounge, etc.? You can have up to 12 receptacles on a circuit but this might be limiting. Could I put one 15A circuit per room for receptacles then do the entire apartment lighting on one dedicated lighting circuit (6 rooms)? (c) I'm thinking of tidying up this mess by taking the wires through the floor of the kitchen, ceiling of 2nd floor and then to each of the rooms after that. Is it worth putting a big junction box / sub panel in to manage that or not?