Lightbulbs with a higher lumen rating work better, yes. And the best lighting for vegetative growth is one of higher kelvin rating --- as in, if it's daylight spectrum [ 6500k, I presume on those bulbs ], it would be better than say, the color temperature produced by a warm white bulb [ 2700k - 3000k ]. The higher color temperature will promote bushier growth and slow internodal spacing drastically.