On my own memory,

The Black Panther is not really a light racket, it's more like a slightly lighter and faster Astrox 77pro. Its even balance, head heavy.

All the rackets that you've listed are headlight but stiff,

It’s a very good racket but not for everyone. Within the category of head heavy it’s definitely not as head heavy and the 4u definitely felt lighter than other 4u’s I’ve used. Power if you can find the right timing is very good for how light and how less hesd heavy it is. I wouldn’t necessarily say it’s a difficult racket to use as it doesn’t require a ton of strength/swing speed to extract the power out of the flex, BUT it’s difficult in that you have to really click and learn the timing which for me I was on and off with so eventually sold it to a friend who did manage to click with it better.

For reference I am also a speed guy, and my experience is with the following rackets:
- OG Astrox 77 (3u)
- BS 12 (3u)
- Halbertec 8000 (4u)
- 88d pro 2nd gen (4u)
- Astrox 77 pro (4u)
- ars90s (4u)
- ars100x (3u & 4u)