Need some reflectors on the backs of those bulbs to direct more light to your plants. Just tinfoil right on the backs of the bulbs works great. Takes a little fussing around but you can cut pieces so the back end ties around the base and a tab on the front tucks in to hold the foil in place. Can easily double the amount of light that hits the plants.
The way your lights are set up you could even blanket the back sides of the bulbs with foil like a cone to direct light downwards. Shiny side on the inside.
I grew my first buds back in the late 70s then on and off as life, and kids, got in the way but have been at it steady since '01 now. Not as much fun as it used to be but soldiering on.