Back in the days when Tyrion ruled the show

I still love Tyrion but he obviously hasn’t been the same since his trial. But having your father sentence you to death will most likely screw any of us up.

The book character takes a sordid turn, which is well in keeping with GRRM's predilections and might turn up more entertaining but not necessarily deeper. He should have been eaten by lions in the arena but the lizard bitch kept them starving  
Talk about plot armour…

If Tyrion is a piece of sh-t it’s due to piss poor upbringing. You can’t raise a child to hate himself and then expect great things by him. So if anyone is to blame it’s Tywin.

Fuck outta here! Tywin wanted Tyrion to be grateful he didn’t have him killed as a child. All Tywin cared about was his family’s perceptive strength and all it did was cause his own family’s downfall. Had he had an ounce of empathy for his children the Lannisters would still be a force to be reckoned with instead of a doormat for whoever wins the North, you delusional twat!

Tywin was right all the way about Tyrion. The character is littered with self-pity and targeted at underdog loving leftards.

There is no doubt about Tywin's flaws but they were general. Tyrion was even made to say it himself in S3 when discussing their planned marriages to Sansa and Loras with Cersei: "Father doesn't discriminate". 

Compare Tyrion with two parallels, Jon and Sam, and see how differently they react. Jon is rejected by Catelyn and his supposed father lets him go waste his life at the Wall without ever telling him the truth about it. Arsehole Ned cared for Jon less than Tywin for Tyrion, it seems. But then, Dumbned also thought there was honour in taking the black, so that may pass as that, yet he acted undisturbed as his bastard "son" decided to get lost some place no one cared. He had no use for him. Now Jon does grumble quite a bit over it, even avoids whores in case he would father another bastard, because being raised by the richest family in the North is "not a good life" but he never falls into resenting his family. He is hurt when Ned dies.

Sam's rejection story goes further, and he certainly has no love for his father but he barely ever says anything bad about him. "My father is… my father" he will tell Gilly, that's about the most vindictive we'll see him, and Sam does all he possibly can to find a place of usefulness in the world. Sam, as a fat coward who likes reading, is just as unfit to live up to generic expectations as Tyrion. He doesn't even have money to compensate for it but he develops a loving, forgiving nature when Tyrion slowly grows hateful and turns unto a patricide then joins his family's worst enemy.

The difference between Tyrion and Sam is telling: Sam's father is a bully demanding the impossible. Sam doesn't take him seriously, makes his way around him and grows. Tywin, on the other hand, is right about Tyrion. His reproach is of Tyrion's behaviour, not of his nature so it hits and hurts. Tyrion grows resentful and withers. He accuses the world of discrimination so he can dismiss the responsibility for his own weaknesses.

Tywin, S3E01: "I gave you real power and authority. You chose to spend your days as you always have, bedding harlots and drinking with thieves."
Tyrion: "I am on trial for being a dwarf."

So book-Tyrion turns into a villain in plain sight, hoping to rape and kill his sister when he returns to Westeros but show-Tyrion was turned into a bad joke teller with mild regret at seeing his countrymen burn. Pity.

The best for the realm would have been for Ned to continue lying to Jon and invent something about "Wylla". He could have trusted Catelyn to keep the truth to herself too but that shit never cared for people, only for principles.
I never thought of Tywin taking "a victory lap" with Shae, there was nothing to indicate it. She was just a whore to him but Tyrion let himself be triggered again. Viewers are meant to cringe at his misguided assumptions, the same way they are to do at Jorah's blind optimism that Daenerys will be the perfect ruler. Tyrion himself is the one whose scepticism makes it visible when they discuss it in S5E06, which is a pleasant duality. The clever man who sees right through other's blindness is blind to himself.

Jorah's irrationality was perfectly exposed. "Have you ever heard baby dragons singing?" is hardly a receivable argument to someone's ability to rule.

Tyrion's conversion after Daenerys just listened to him twice was less convincing but this was Season 6 and barely any of it made sense. The writing just jumped to wherever it wanted characters to be: "For what it's worth, I've been a cynic for as long as I can remember. Everyone's always asking me to believe in things: family, gods, kings, myself. It was often tempting until I saw where belief got people. So I said no, thank you to belief. And yet here I am. I believe in you."
Long talk, no real justification for such a change. One episode, one battle before, Tyrion was trying to hold her back from behaving as a ruthless tyrant dragoning everything in her path.

And that should have turned him off. The Kinvara scene was there to show that Daenerys' rise was the occasion for an ominous and unwanted power to rise with her. Tyrion should have seen that the new alliances would be a bag of knots installing a new mess in place of an old order which is only detrimental and "oppressive" in the mind of dumb viewers. We never saw the Lannister rule being oppressive or worth removing in any other way than for the personal benefit or misguided convictions of those who tried.