As I explained on Twitter when I switched from horse: "Panther came to fill some gaps: comfort; relaxation; more comfortable with my body, my and others' attractions, and expression of affection; strong AND soft for others."

I'd add that panther facilitates a sense of self-confidence, both because of increased comfort in my body and because of big cats' claws and teeth and power that can provide a formidable defense.

Interestingly, I've also observed that the D&D class that characterized horse-me was cleric, but as panther I'm more of a bard. And that's played out, however strangely: as a horse, I could write blog posts and history and such, but I wasn't as comfortable with most fiction; since panther, I've written more than I ever have.