Even though the Township system allowed all of your party members to chime in the current story arc with both private and public conversations with Ryu, it did limit the opportunities the party had to interact with one another.
Rand for his part expresses at one point that he see's Katt as a daughter, which actually does make a certain amount of sense given her lack of maturity, and his age and stature, but the game doesn't actually develop a relationship between the two. It's just like how Katt calls Rand's mother aunt or grandma, but the two never interact with one another at any point whether she's in the party or not.
The game does provide you enough dialogue to give a fairly concrete impression of the interparty dynamics, what the different party members think of one another and such, and each character gets their own story arc after being introduced (well, Spar and Deis don't really get their own.)
Basically the game does enough to establish that there's more going on than meets the eye. The party is fairly balanced, and even though Bow and Jean basically have their story arcs concluded after the first 3rd of the game, everyone gets their moment to shine, and isn't really tacked on or a loose thread.
Pretty good for a 24 bit game.
(I'd say Breath of Fire III had the best cast overall in terms of development and balance)