Defoliating the auto on the late flowering stage

LST if possible to increase airflow and light to lower nodes.. I would not be trimming 30%-50% of the leaves that will set you back 100%. 10% defoliation bit more realistic.

You need air circulation it’s very important.

There is nothing to worry about, it’s much better removing the old big leaves to open the plant up. To prevent bud rot and getting more light. Try to take the leaves that’s block lower bud sights of light and the old dark leaves. Good luck my friend and may the buds be with you 😃🔥

Take off as few as possible if concerned about WPM or other pathogens. Light penetration is not necessary. Apical dominance is why the higher buds on plant get the most resources. The products of photosynthesis freely flow through the phloem at all times all throughout the plant. Where those sugars are used is not dependent on where the light hits. leaves are also lungs. CO2 intake is equally important to the amount of light you provide.. it is the limiting factor for your light, so don't limit CO2 intake as best you can.