@ShutterShock did a great job answering your questions for me 
To address your unanswered questions:
I personally use off-brand threadlocker because Loctite isn’t popular where I’m from, but for information about the different types of Loctite threadlocker we have 2 great threads in the Wiki section of the forum:
Threadlocker (Loctite) Guide - Wiki
Where should I use threadlocker / Loctite on an electric skateboard?
Yes, 2-piece wheel pulleys suck because they’re hard to center, sometimes go off center, and can fall apart on you. 10$ more for a press-fit pulley with its own bearing to keep it aligned is 100% worth it.
I use Vesc FW 5.2 as well rn because I’m familiar with the known bugs it has and how to work around them. I’ll switch to 6.0 soon after more people have tested it. Some people got hurt on 5.3 so I don’t trust it personally.
What I love about metr is that it logs remote input, which makes diagnosing issues a lot easier, and it has a very nice online log viewer which makes sharing and viewing logs very pleasant.
Soldering bullets together is a pretty crazy but also pretty genius idea 
Maybe I’ll try that 