in the mission general mobilization i bought the 100 unbound rune packets and then i bought 8 charm packs (i used 60 coupons to get the last 30 points), but if you own enough coupons to do it then getting hinata could be not a bad option if you don't own any better ninjas (she isn't half bad, overall for azure fang + roshi).

in time limited shop i bought summon scrolls because there was the rebate on, so i managed to reach the 80 counter, i considered the ninjas/summon options there too expensive for the concrete advantage they grant (aka if you are f2p don't buy them).

in fishing mania too i bought only unbound runes packet. Unless you are in a serious lack of medium refinement runes (i'm not) then unbound rune packets are always better.