Hello, I hope you are well. I contracted HPPD about 8 years ago from acid had a period of abstinence in which it almost entirely went away with the exception of the occasional 'flare up' usually when I was feeling anxious. I then had a period of 7 strong mushroom trips in about 7 weeks that seem to have brought it back to some extent so i am stopping psychedelics for now. I too am very interested in their mechanisms, applications and pretty much everything about them. However they CAN induce a detachment from reality which scares the shit out of me. Life is amazing and for a time psychedelics made me feel this in a deeper fashion however there were breaking points where I felt like I wasn't myself, detached from everything and everybody. This is not where I want to be. Be careful. My advice would be to take a long beak and see if things get better. Exercise, sleep and meditation are excellent tools to use to get out of the funk. It sounds like you just have visual distortions and not DP/DR; I think that's a much more manageable situation than what a lot of other people are facing. Quit while you're ahead before you lose your sense of self and place in this world. Also I think that it can lay 'dormant' within your brain, in which it is susceptible to reactivation. The moral being if you think you're 'healed' and go back to tripping the previous effects can come roaring back. I have gained a lot from psychedelics however I paid some prices, I think that for a while I was deceived into thinking that they were the answer. I really don't think they are the answer to anything. They do allow you to see beyond yourself and feel/know there's something greater than you out there, that we are all one and love is paramount to everything. However, these conclusions and facts exist independent of drugs and can be realized through meditation and mindfulness. There's a great quote from Allan Watts about the use of psychedelics "...when you get the message you should hang up the phone"
Anyway I wish you the best of luck, take care.