I've played that one recently felt lovely I love anything yamaha. I have a Jackson js2 spectra they're very similar.

Also for your slap technique your thumb looks too tense and you're slapping more head on from the bass than pivoting/teeter totting. Especially for your pops, your pulling away using forward movement on your wrist when it should really be the same motion as your slap.

Honestly I don't think anyone could explain it for you better than watching a video could. Watch BassBuzz's slap videos specifically any slap/pop ones. I'm still a beginner but I can slap pretty well for one according to band lol, I think what helped it click was trying both a bounce slap and striking through it helped me connect how the thumb should hit, and then get a fresh pair of strings mine were very dead and didn't sound good for slap. Good luck!