Veg time is crucial. If you up it to 8-10 weeks you're gonna get thicker stems, hence more liquids will be transported by the plant, and this translates directly to denser budz. Another thing is making light exposure as efficient as it's possible. And this neans LSTing, SCROGging and defoliation. Another thing is not cutting down on nitrogen until late flowering as plant needs it to build cells and uptake phosphorus (surprised?).