Disclosure: I only stuck around until the TNG original class graduated.
Here's some unpopular opinions:
1. Rick alone was to blame for Jimmy getting shot. Yeah, Spin contributed to Rick's angst with that lame prank but Rick alone did it and instead of everyone dumping on Spinner, they should have all dissed Rick's memory. Oh, hated how Snake just spouted off jargon to Radich instead of pointing out that Radich ignored the biggest 'warning sign' re Rick's violence- he'd put Terri in that coma and Radich was wrong to ever let Rick return. Snake also failed Emma by not getting mad at Rick when she told him he'd pointed a gun at her (his new daughter). Instead of working to guilt JT to show up at Rick's funeral for Toby's sake, someone should have tried to tell Toby that a big part of growing up is that everyone can make mistakes in picking their friends and he could use his bad pick of Rick to learn to pick better next time.
2. JT's 'little problem' was easily the most tasteless and potentially exploitive (for the performer) storyline. Imagine had it been about a flat chested girl who'd been exposed in front of her so-called friends and love interests or a kid who'd had keloid scars from cancer. Would anyone with any real compassion have thought it funny to have seen her continually dissed and her continually feeling shameful over it? They made a big point to have all Terri's friends and other kids rally around her and shut down Mohammed's dissing her for being plus-sized but they didn't do anything more than treat this as a joke for JT. Not only did Manny and Liberty not act like real girls and avert their eyes or tell Liberty's snotty kid brother Danny that that was no way to treat a houseguest, but they joined Toby (who himself deserved to be called on for having done that to his supposed best friend) in derisively laughing at JT's anatomy. Oh, and why didn't anyone on the show wonder why Danny was obsessing about his sister's friend's anatomy. Not only did the producers openly say they thought this rather crude, juvenile and tasteless joke was the 'funniest' gag ever but at no point did any character ever apologize to JT for having treated him so shabbily. They all literally let him die without expressing any regrets over their unfair,cruel actions. Is it any wonder the performer asked to be let out of the show even if it meant the character's death?
3. If Manny truly hated being called a slut why didn't she just tone her wardrobe down to what it had been a few episodes earlier? She sniffed about how Craig was dating Ashley when they hooked up but no one bringing it up but she herself hadn't yet broken up with Sully so no points for righteousness there. Oh, and why were the producers so intent on showing how 'hot' she was supposed to be in that new wardrobe? Hello, the performer was barely in high school and they could have conveyed how others viewed her without all those close up shots! Talk about exploitive.
4. Hated how they were so intent on keeping Craig as an object of pity, that everyone excused away his beating up the much-smaller Joey as him being 'bipolar'! Hello, he knew what he was doing just as Rick had. Joey had given him refuge from his own abusive father and, when Joey actually confronted him over having stolen his credit card and caused so damage, Craig did THAT to him under his own roof- and in front of Joey's own child and love interest! I always thought Joey should have told Craig he'd visit him in the psych ward but that Craig could no longer live there! Sorry but no one should keep an abusive thug living in one's own house who couldn't have cared less who he hurt or that he'd needlessly traumatized his own little sister.
5. Along those lines, hated how they made the goth-but-smart Ellie become a total airhead to fall for Craig even knowing ALL he did to her best friend Ash and everyone else.
6. Kevin Smith. Funny in very small doses but a drag for more than two minutes. Why did they let him monopolize over several episodes? Perhaps Joey and Caitlyn wouldn't have worked stuff out but surely they could have come up with a better catalyst than Caitlyn getting entranced with Kevin Smith? Also, bogus how every single character laughed at every single line of his as though it was the funniest and most brilliant thing they ever heard- even those characters like Ashley, Emma, Paige or Snake who would have more likely rolled their eyes or just groaned. Should have told him to just do a 30-second cameo as a convenience store clerk if he wanted to be on the show at all or just stay home. Boo.
I'm sure I'll think of other stuff but that's all for now.
ETA- spelling and addendum