I am the author of TeX Tutorials on Youtube (although I have not had much time to make new videos).
I am currently using XeLaTeX professionally in conjunction with a version control system and the automatic generation of many documents. I suppose that makes me at least nearly a TeXnician?
- Xelatex because of the unicode support.
I am a supporter of up-votes for good questions (not just good answers).
My favorite package is tikz (and tikz-qtree).