First off, welcome to the Nexus. Nice to have you.
A pleasure to have another mystic psychonaut with a decent amount of experience under their belt... and a meditation practitioner no less.
A hearty welcome indeed. I think you will enjoy being here, and your carefulness and patience will serve you well. There is a lot of good information here, and a lot of really good people as well.
As for your Q's:
1) It certainly doesn't hurt to keep the soup and try pulling more, esp. if you try a different NPS that might pick up things not picked up by the one you used originally. If you were meticulous in applying the tek, there will be minimal alks left, but it is like a tea bag in that it is never really fully spent... you just get to the point that it is not worth messing with anymore.
2) Going for enhanced leaf or changa is not necessarily preferable, but it does make thing easier if you are not familiar with vaping FB or don't have a good device. Changa is the easiest route because the harmalas help to ensure that you will get the dose, and you can smoke it just like weed... which most people don't have too much problem consuming.
Anyway, welcome once again. I hope you find what you are looking for. Prepare to be amazed.
HF
"Curiouser and curiouser..." ~ Alice
"Do not believe in anything simply because you have heard it. Do not believe in anything simply because it is spoken and rumored by many. Do not believe in anything simply because it is found written in your religious books. Do not believe in anything merely on the authority of your teachers and elders. Do not believe in traditions because they have been handed down for many generations. But after observation and analysis, when you find that anything agrees with reason and is conducive to the good and benefit of one and all, then accept it and live up to it." ~ Buddha