I'm hesitant to encourage viewing self-guided tripping as therapeutic in a clinical sense - it doesn't sound like you have any intention of reading it this way, but that sort of advice might be misread by others as "stop going to professional therapy sessions and drop acid at home instead!" So just as a clear disclaimer: I would only ever recommend psychedelic psychotherapy, particularly of the self-guided variety, as a supplement to more traditional approaches, not an alternative.
Now that that's out of the way... I actually went through a CBT-based group therapy program quite recently. I used MDMA a couple times during and immediately after that program and found it very helpful as a way to process my experiences in therapy and reflect on some of the emotional insights that sober CBT techniques led me to. I haven't yet thrown LSD into the mix, but I can definitely see a light to moderate dose LSD trip as potentially valuable as well.
I would probably not recommend delving into any really raw or intense issues while tripping alone - probably not the best way to, for example, try and process a traumatic memory of childhood abuse. It might be helpful, but it also might be a recipe for a really intense bad trip that will only make it more difficult and painful to work through the issue later. A lot of less intense applications of CBT methods could be valuable, though:
* Mindfulness / diaphragmatic breathing: I think a lot of experienced trippers probably do these or something very similar to these while tripping already, in the form of meditation. This could be a useful addition to any tripper's arsenal, even when tripping for purely recreational reasons; if you have the presence of mind to ask yourself what you are currently thinking, feeling, and experiencing, it can be a great way to help break out of unpleasant thought loops or just 'ground' yourself a bit if things are getting overwhelming. And since LSD's effects have a funny way of manifesting wherever you direct your attention, a mindful tripper can sort of guide the direction of the trip simply by directing one's awareness to certain thoughts or feelings.
* Identifying primary vs. secondary emotions: this is a lot harder to do when you're still actively immersed in the emotional experience you're trying to analyze. Again, steer away from intense/traumatic issues, but if you're trying to make sense of your emotional reactions to a certain everyday situation, tripping might give you that critical distance from your everyday state of mind that you need to see what is really going on emotionally.
* Opposite action: you mentioned perfectionism which produces anxiety - so how about trying to practice a skill or hobby while tripping, and letting the end result take whatever shape feels right at the time without worrying about whether you followed some plan or applied some technique perfectly or not? It might be easier to be comfortable doing something imperfectly when you have the "excuse" that you're tripping. For example, if your perfectionism sometimes takes the form of writer's block (you don't want to make any mistakes or write something that doesn't fully express your mastery of the subject matter, which makes it hard to get started writing anything at all - I know I've frequently had this problem), try writing stream-of-consciousness.
* Cognitive defusion / reframing: if there's one thing psychedelics are known for, it's causing you to look at things in a new way. Sometimes a nonsensical new way, sometimes an insightful one, but different in some way or another. If there's a particular idea or chain of thoughts that you've been struggling to move past in your sober therapy, think about it while tripping and see if that changes what you see as true, meaningful, important, etc. It may help to clearly write out the particular thoughts or subjects you want to work on, how you think/feel about them normally while sober, and what you want to change about your thoughts/feelings/actions. On a similar note, if you have any behavioral habits/tendencies that you are struggling to understand the source of, and you find yourself doing them while tripping, you may find it easier to figure out what was going through your mind while you did it. I often find things that my sober self takes very seriously to be silly and amusing while tripping, and sometimes that's exactly what is needed.
I wouldn't recommend pushing the dose up too high - IMHO, this sort of use of psychedelics is really best at fairly low doses. If your thoughts are *too* altered, you will both find it harder to do any of the above steps and harder to remember any insights you reach during the trip once you sober up again. I think the most helpful thing you could do would be to plan out some of the above ideas and maybe write yourself a to do list of sorts to remind yourself what to do next while tripping.
