Well, that depends on what team you're gonna use or what Main Class do you wanna use? .. Each ninja you've said above are both good, Minato Jonin and Kushina Habanero are good together, just like what sir Jibu said .. I've seen a lot of people using teams that includes Minato and Kushina, together with Pakura or other support ninjas .. On the other hand, Roshi is a great ninja too, specially if you can manage to fully buff him by stacking him enormous amount of Life and Defense, he'll be immortal in no time, believe me .. But the said ninjas can be more good or be more effective with using specific Main Classes (only my opinion) ..

Minato and Kushina can be best to pair with Wind Class, but some people choose to pair them with Fire Class .. Roshi is most likely to be seen with Water Class, majority of Roshi users while other using him with Wind Class together with Ninjas like Fuguki and Kurenai .. But if i'm gonna choose between the two sets of ninjas, base on what you've said .. I'm gonna prioritize or pick Minato Jonin and Kushina Habanero, just add Kurenai Fully-Skillbroken or Iruka and you'll be fine .. Roshi, is better with Sakura Sailor and Han or Fuguki, of course with Water Class ..

Take advantage of how Great Plates drop Kushina's Fragments, one day, you will find her very useful .. My 2nd main account already recruited her and my main account is waiting for last 23 fragments of her for me to upgrade her stars to 4 .. But i'm just relying from the free keys i'm getting daily since my coupons are for Lucky Stars only (Angel Konan) ..

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