I usually prefer a two-shield Rune and Raja, and I'd pretty much always prioritize the party order as:
Wren, Demi, Gryz, Seth, Alys, Chaz, Rika, Kyra, Hahn, Rune, Raja
I should probably re-think that when I'm doing two shields on Rune and Raja though. Rika's got great natural defense with her high agility stat, but she's very vulnerable to techs (etc.) with her pitiful mental; I should probably keep her at the back more often.
Right now in
my gratitude challenge, Rika and Alys have ended up with two Crmcshields so I've been keeping them at the front. Having always kept Gryz or an android at the front of the party I find it pretty refreshing to see Rika saying, "How boring!" every time I check nothing.