I would say save 300 seals scrolls for seal scroll rebate and put them into GNW treasure. The rares are good and people are still using them. Also both super rares are good with the respected teams. The other super rares arent' really used much these days. Fourth Raikage is great with skill breaks, but think he has to be 4 star. Not sure how good Sasuke is with skill break. I would say * with GNW treasure. You c*so piece together ninja in the collect tab in the mean time.

I see plenty of KCM, Madara, Jinpachi, and Sasori at level 100+, so they are far from extinct. Also it's untelling how long it will be before we get another treasure. Never know though it seems Oasis wants to release new things when CN does.