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?

[attach]97214[/attach] This is a drawing from the electrical box in which there is 2 switches. It's a house from 1961 with ungrounded wiring in this part of the house. I was about to install a programable switch for my exterior lights consisting of 2 lights in the soffits and 1 by the address. The lights were wired through 2 switches, basically one just enable the other one but the 3 lights just worked when the right switch was and then the left one could work. When I opened the box I notice wires coming in from 3 sides as the schematic in the drawing. 72 volts was coming from the bottom right wires and there was a jumper between each switches. I just removed the 72 volts wires and wired everything to just 1 switch with the 120 volts wires. Everything works fine but I thought that was quite weird. Any thoughts on what might be going on?