Dexter should have ended before the it's-technically-not-incest
I think, the "good" place to end things compared to the travesty that followed was the penultimate season where Laguerta tried to catch Dexter. The original idea for ending was that entire series is just Dexter's flashbacks while he awaits for lethal injection on a death row, so Deb choosing to catch him instead of shooting Laguerta in penultimate episode would've worked perfectly. Fuck, even her asking him "remember the monsters?" would've fit there.
They did ok with the whole arc where he built a new team and then for a season or two after that, but once that whole bit where he hallucinated a relationship with Cuddy finished and it wrapped up there, the show should've just ended with him going into the asylum.
Don't get me wrong, Hugh Laurie acted his ass off for that bit, but to then go and try to actually answer the "will they/won't they" between the two was a bad idea.
I think, penultimate season's ending would've worked fine. We had every possible plotline resolved and House chose not to LIVE IN A SOCIETY, so him saying "fuck it" and leaving would've made sense. Instead we've got more literally who's and the rehash of old shit for 100th time. Fuck I even remember there was an episode about faith in the last season and it didn't end with usual "they prove it was a disease, believer agrees, but choses to keep his faith", no, they had some limp dicked "oh, we cured him with this - but that's a regular medicine! I DON'T BELIEVE YOU!"
Invincible should have ended after the Viltrumite War. It's just a car crash in slow motion from there.
Invincible should've ended on season one and that's me being generous. What was afterwards was a travesty. I remember watching Omniman going psycho and thinking "Jesus Christ, if he is so crazy then what about those who are even stronger than him?". Then season two comes and it is just neverending "oooh, next time we're gonna kill you!" And then turns out that they have a number of obvious weaknesses that nobody have figured out despite entire galaxy shitting their pants at a prospect of facing them. This is so stupid.
WestWorld
This went on for way too long. Season one was excellent and season two was somewhat fine, the next seasons were watching it get shittier and shittier. Things stopped making sense, too many twists that weren't not needed at all. Pacing was a fucking disaster, tried going way too into depth while forgetting about the action, and the characters were not consistent at all. Scenes were rushed or took way too long.
Season one was a mixed bag to be fair. The stories of Black hat and a man who fell in love with an android were awesome, the rest however... Especially the one with robohooker. "I want you to increase my IQ. - No, we can't. - OOOH, I DIED SO MANY TIMES, WHAT ABOUT YOU? - Ok...(" Yeah, no wonder shit fell apart.
Season 5 is an obvious place to stop, with Sam in hell forever, Bobby and Castiel dead, and Dean meeting up with Lisa and presumably settling down. They won, but at a tremendous cost. You just need to not include the last scene of Sam coming back.
IIRC there was a different ending if CW didn't pick them up for another season, with the details being largely the same, but Dean also dies and goes to heaven.
IMO it all went to shit when they started introducing more and more supernatural stuff and angels, who are almighty and not restricted like demons being too stupid to catch two regular humans... To me it ruined everything. If it ended on season 3 with Lilith killing Dean and Sam killing Lilith it would've been better. He would end up where it all began minus his girlfriend and there would be a sense of irony - he tried so hard to escape his family and now they are all gone.
My picks:
- Prison Break. Everything that was after season two was stupid and unworthy of any attention. Probably, because if you call your show Prison Break, you should end it when people actually escape prison.
- Bones. I was only able to stomach the first season and this shit had what, 12 of them?! How in the fuck?!
- One Punch Man. I mean, it was funny to think about, but in essence it is just that - one note character. How long can you drag this joke around?
- Fullmetal Alchemist. This is why original series WITHOUT OVA is much better to me than Brotherhood. It is also... More mature and less shounen? I don't know why people hate it so much.
- Buffy The Vampire Slayer. It was just too long and too ridiculous. Same for Angel which I liked way more.
- Obvious light years long shit like Naruto and especially Bleach. The latter was chewing on the same shitty concept of "here are enemy ranks, let's go from the bottom to the top, but it's squad captains, then it's numbers, then it's letters". The whole quincy arc was even more retarded than a previous one, somehow. It should've ended with Ichigo beating up Aizen and losing his powers, but Kubo had to pull YHWA out of his ass. One Piece is not here since I was never a fan and do not plan on becoming one.
- GANTZ. It worked better than a rather short story. The further its author went the more ridiculous it was getting. The last arc and especially ending sucked ass. The OVA worked better with Kei jumping under a train after the shrine mission.
- Berserk. Never was a big fan of it, but Miura should've stopped where the TV series stopped if he had no idea how to continue.
- Someone mentioned John Wick should've ended after the first one. I disagree, they just should've made the third movie that had element of the third and fourth and wouldn't be ALMOST THREE FUCKING HOURS, IT'S AN ACTION MOVIE, ARE YOU INSANE?