Part 3:

Remove potency from Leaden fist and spread it more evenly across the rotation
I agree with this. Specifically, instead of putting all their eggs in one basket with LF only adding 150 potency to Bootshine, spread that 150 evenly between the 6 single-target primary weaponskills, so +25 a piece. Then it becomes like Blunt Resistance Down, only now there's no confusion as to what it does. It's the simplest way to propose this solution in concrete terms.

Remove fist stances
While I agree FoE is pretty useless in its current incarnation, I'd disagree with you about FoF and FoW.

Firstly, in certain high-speed rotations, being able to switch between the two is necessary in order to maintain viable damage output while trying to get your stacks up.

Secondly, you have to remember that while some MNK mains like to go fast, a) not everyone is comfortable with high speeds, and b) not everyone has the ping to handle a ping-dependent job. The fists allow for a player to modulate speed based on their personal comfort while maintaining damage output. This was done in order to make the job accessible to a broader demographic of players. Getting rid of it and forcing MNK into a baseline speed would outright ruin the job for many players, so this idea would cause more harm than good.

Lastly I'd rework Anatman to give 1 or 2 stacks of GL instantly with no channeling.
Please re-read my post about putting the 5.1 version Axe Kick into PvE. It works for single-target fights, it works for dungeons, it slices, it dices, it cooks, cleans and does your taxes. Leave Anatman for things like phase transitions and just get rid of the silly-looking Form Shift spam to keep stacks up, as it wasn't even in SHB to begin with and was only a band-aid measure. If you're concerned about chakra gains as well, just add in Somersault to boot, because it would just give a chakra stack and help give players a bit more control over their chakra gain, so they're not left hanging with 4 out of 5 chakras and unable to tFC when it would be ideal to. Leave their PvP effects, give Axe Kick 80 potency like AotD and Somersault could have a lower potency as well, like 120 or something to that effect.

This is a very simple solution to a lot of MNK's problems. That, and just slightly buff TK and shave off two seconds from its recast time, so those of us who know how to do the SHB version of the TK opener can do so without it not being so worth it, and without having a weird GCD clipping issue if at specific odd-numbered GCD speeds (e.g. 1.87, 1.85, etc.). It doesn't rely on massive reworks or reinventions to the job, and it can literally be implemented and tested within the hour without having to rework job-wide potencies.

Anything else is just too much work. Keep the suggestions simple and you're more likely to get what you want, sooner rather than later.