I understand that it seems like a million variables for the grower to contend with, but like anything, they are manageable if you can focus one on problem at a time. Make a priority list with the most important features on top. I would expect to see things like "shorter, bushier plants" and "increase the number of growing points (bud sites)" near the top of your list. Then set out to improve on the things at the top of the list. For instance -- the first thing one does to get shorter bushier plants is to research the varieties available. Some, like one of my faves Armageddon, rarely grow more than 36 inches at harvest. With that info you know to fit fewer pots under your flower light as the adult plants will be shorter and wider. But most of your successes will be the result of trial and error. Early on I was having trouble getting my clone operation going. My success rate was dismal. Then I forgot to moisten the pellets in the dome one weekend and discovered a million new roots. I had been keeping my jiffy pellets too moist in the dome. {sound of light bulb turning on...}.
Good luck, BigSteve.