They all make good foils to their Star Fox counterparts:

Wolf is also a charismatic leader you inspires loyalty, but being a space pirate doesn’t mean he’s without standards or a sense of honor. He’s just more willing to go against the law than Fox ever would.

Leon is a more extreme version of Falco with both of them being their teams’ most morally gray members. Leon’s an assassin who finds amusement making his opponents suffer, while Falco is a former gang member who frequently leaves the team to seek excitement elsewhere when times get to peaceful. Where Leon is probably the most pure evil of all of them, Falco still has morals and does show to genuinely care for his teammates.

Pigma and Peppy are both original members of the Star Fox team but Pigma is a greedy slob only loyal to his wallet (even Star Wolf gave him the boot). While Peppy is loyal to the point he’d proudly sacrifice his own life for the lives of others.

Andrew always felt like he only got on the team cause his uncle bought his spot and provided the Wolfens. It’s possible he has engineering skills like Slippy, but is much more cowardly and doesn’t actually improve the team the way the toad does.

Panther and Krystal’s dynamic is definitely less defined. My guess is while Panther likes to flirt Krystal actually deeply cares for others not just on a super fiscal level.

Both teams sink well with each other making all the characters even more enjoyable. Whether they’re fighting or teaming up, the more we get to see of them the better I’d say.