Katekyo Hitman Reborn!
far too rushed ending. plot had too much potential. could have continued how the former arcobaleno grew up. how tsuna met giotto. how tsuna chose reborn, not any of the girls. how he ruled the vongola. what happened with the varia, with byakuran and yuni, with checkerface, with bermuda and with the other arcobaleno. it had too much potential and they let it go to waste. damn it.
Naruto
great plot. could've been better, but meh. should have been yaoi since naruto is so focused with sasuke but I love hinata so okay. Sakura can go die however. awesome plot twists on the 4th great ninja war but it was too dragged out that it became somewhat boring before the end.
Cage Of Eden
Gotta be honest. saw the ending waaaaayyy before they even got to start piecing together the building locations. but I honestly hope that it wouldn't be like that. too many fucking plot holes. I wouldn't call that open ending. that's a 'fuck this. im tired. lets end this already' ending. no resolution whatsoever. vague romance hints at the end. if one isn't critical, it was really great. the early plot twists were good. had be hooked for weeks until I caught up to it. the character progress was a bit rushed since they really have to. plot progress for the first volumes was great but by the end it was really rushed. one too many information in one sitting. the trivias throughout the manga was kind of useful. the psychological aspect of the manga forever changed me. one of the best underrated manga there is.
Shingeki no Kyojin
Really good but you'll come out the fandom like a war veteran that has PTSD issues.
Apocalypse No Toride