For residential we put 8 to 10 recepts per 20A circuits. No lights on recept circuits. All lighting circuits are loaded to 1800 watts and we calculate the maximum fixture for the outlet. If its a bedroom we figure fan with 4 bulb light kit, 60 watt closet and so on.

I know we wire heavy but I picked up a contractor because his electrician had a long run of 12 with lights and recepts and when the home owner plugged in an iron the lights dimmed and flickered. That contractor spends about $150K a year with me now.