I'm not sure if making hat spin more minus is the right answer. All of those characters besides Kano that you named, have 50/50s.
With 112124 and B321 there are different options to stagger. Deciding to poke out when he can stop at 1, 11, 11212, or with the other string, B3, or B321, is very problematic. What keeps Kung Lao sort of in check with the B321 string, is that his fastest normal is 8 frames, so I personally view that string as fair. You can armor or backdash through the hat spin, B3 is -3, and B321 is -5.
A couple of potential nerfs, that I don't think would hurt the character too bad, are nerfs to his 112124 string, and F2. Making F2 a high is probably a good idea. It'll still be very useful for punishing and pressuring, but Lao's will have to make better use of a slower mid in B3, and D4 to get in. Also, making either 11 or 11212 a bit more minus, may make this string not as powerful. I don't know. Just my thoughts.
I know people will chant for jumping 2 nerfs. I personally feel like this move is completely balanced, in most cases. I know, come at me bros. It's 10 frames, so in a lot of cases it'll lose air to airs. Sometimes i'd rather have one of the many 6 or 7 frames jump ins, that also have decent range. Maybe make it a little shorter? Anything severe would make the move really bad in comparison to a large amount of the jump ins in the game. I would personally swap for Shinnok's jump 1. I don't know how other Lao's feel, since jump back 2 atm is really strong, but a 6 frame one with pretty decent range, is definitely not a bad trade.
I don't think I could really accept a nerf that makes normal hatspin punishable. You're kind of killing the essence of the character. Maybe he could receive 50/50s and a vortex, like Ermac? Lol, but again, killing the essence of the character. I think he's meant to have the move, the way it is. Nerfing other things is the answer imo.
Good podcast btw.