Honestly, out of the three sisters...I think Renka is the better of the three...one's a dumbass, and when the dumbass tries to think, the surrounding area goes up in flames...literally. The other is a conniving little bitch of a loli. So Renka, albeit being a hotheaded imbecile...is actually the most stable out of the three of them.
And the only problem with Jasmine is once you've played through the main story...you can never look at her the same way again...(Spoiler alert...it's Asuka's Grandma, Sayuri...the old hag...she uses some sort of ninja art to reverse her age and it...nope, I'll save that last detail for you guys to find out yourselves...)