I'm new to organics too man and I have alot of the same problems you've mentioned. I had some recently that were perfect all the way through veg, but within 2 weeks of flower, they were all fucked up. I also get the yellowing on the leaf margins. It seems to only happen in soil with organics. Also it seems like it happens to me when humidity is low, especially this time of year. Ive read that potassium is easily washed out in soils with alot of water runoff. Unfortunately I dont have any answers to any of this. I've wondered everything from vpd to nutrients. Only real advice I can give is to research the deficiencies and conduct experiments with the clones till u get it right. I'm still trying to figure it out myself! Let us know if u figure out the cure!
What up Bob and thanks for being honest. Your comments actually help a lot in my opinion. It points out that this may be a common problem that others have dealt with. I do have very low RH and low temps giving me a VPD of between 1.7 - 1.6.
Hang in there with me brother we will figure this out.