Btw my last PB was S9 in 9:08 on a 60Hz version over 5 months ago. So yeah that's a crazy improvement.
Not exactly the most impressive grade, but this is my first ever clear (was extremely close to orange line, but the credits came as such a surprise to me that I was too busy squeeling to focus on playing)
That means speed is your primary issue (I think 500-600 TAP is the same as 500-600 TGM1 though?) Play a ton of T.A.Death to train higher speeds. It picks up a lot already at 100, and if you can survive 200-300, relatively consistently you can "easily" do 999 on Master.
I love the visible button inputs. Are you getting the signals directly from a set of arcade controls? I can see how you can easily make this if you're playing on emulator, but the game footage looks like video capture.