A few things I can see from the grow, your temperatures are way to low for this state of growth. In veg the plants love heat and humidity. Your growth is likely stunted right now due to this as well as your lights bring way to far away from your plants. If you do not have them already get a PAR reading tool and a Thermal gun to read the temperature on the plant tops. With 200W lights you will need to have them fairly close.
In veg you should try and aim for min 80s with lights on and no more than 9 degrees less with lights off for veg. As I said they love humidity in veg up to 65-70% is more than fine and they will love it.
As for defoliation i'd wait one more week as it can release a pheromone into the air that signals the plants it is being damages and will shut down all growth for about 24 hours or so. So plan your defoliation accordingly. I would recommend doing it around week 4 of veg for your specific crop other wise week 3 is generally great timing. Weeks 2 and anywhere from 4 - 6 depending on the strain in flower. Other wise avoid ever randomly plucking them.
When you do defoliate make sure to remove any and all plucked leaves from the room immediately. Generally the best thing to do is bag them , seal it right up and get the plucked leafs out of there. For this reason it is very imporant to stick to defoliation scheduling.