What's your budget? Invest in a PAR meter and small humidifier if you have the funds. Get the meter used, save you some scratch. Using a PAR meter to dial in your DLI for each stage of growth will take ALL the guesswork out. It's not hard, either -- there's resources online that you can plug in your readings and it will tell you your DLI based on light cycle hours. Get some adjustable hangers and a torpedo level for your light height, ensuring that between adjusting the light height and dimmer that you have an even PPFD across the whole grow area (or, as even as you can get). If, no matter what you adjust, your PPFD is too low on the outer parts of your grow footprint, then you have your answer -- not enough light power.
The humidifier will allow you to get your VPD correct, which, combined with your DLI being right, gives your plants the best chance at optimum growth (adding CO2 optimizes even more, but another discussion). Get a cheap hygrometer to stick in the area; a small 1-2 liter humidifier is fine if you keep up with it daily. Put the humidifier on a timer with your light cycle so it's off with the lights, but be sure to be exhausting air and oscillating air at all times. The advantage of indoors is how much the environment can be dialed in, which is even more important with us sod-busters -- bringing dirt, and worms, and bugs in the house and shit. You don't want your environment inside running wild. Rein it in. Doing all of this will maximize your yield and quality, which in turn pays for whatever instruments and tools you use to get there after 1 grow.
As for your bud density, don't sweat it. I've only ever been an organic grower, and no matter how tasty or greasy or potent my buds came out, I was always chasing after those dense nugs that I was used to seeing off the street, and, now, from the dispos. Make peace with the fact that your yield and bud structure are probably not going to match what hydro can do, no matter what expensive bloom boosters and carb loaders and nutes and all that other expensive stuff tells you. Some of it helps, but there's no magic bullet except dialing in your own methods and learning the cultivars you grow. Organic soil methods have their own advantages, as it's more forgiving in some ways, and the terps and colors and expressions that the plant displays are unparalleled. If it's bag appeal and commercialized buds you're after, and you think you'll stick with indoor growing, then look into different hydro methods. This is all just advice from an old head, YMMV, but good luck!
