The beginning was a little weak. Not bothering to show us what happened after leaving us hanging last season is lazy writing. Also, it made me focus on Caitlan and her grief over Ronnie, rather than Iris, trying to pick up her life after rededicating herself to Eddie Thawne.
Barry appears to have picked up Stupidly Stubborn Superhero trait. This after lecturing the Arrow crowd how much Ollie the Irritating needed their help. This has got to be in TVtropes somewhere...
I really don't understand why Barry didn't insist on taking the microphone to explain that another superhero gave his life closing the singularity at the Flash Day celebration. I mean, wth. Barry's gonna need to start his trophy room soon.
I thought Caitlan's grief over Ronnie's death and Barry's senseless taking credit for saving the city and Ronnie's not being given credit would be the catalyst for Caitlan to become Killer Frost. Slightly disappointed she seems over it already. Maybe it'll be her doppleganger!
Atom Smasher looked in character. And it was so cute when Cisco hugged Dr. Stein.

I don't feel Stein got enough to do though. I mean, he's a scientist, he ought to be tap-tapping at those computers too.
This show will never be as good if Tom Cavanaugh doesn't come back somehow. I miss him already. That was some puzzling ambivalence he displayed on the recording. Someone needs to write long essays on Thawne's thinking.
Henry Allen's "you can't be a hero if I'm around" was the weakest line I have ever heard. I could see Allen's having issues with reintegrating into the community; everything would remind him of his wife, and everyone would remember him as The Murderer. If they wanted to get rid of him, they should have just had him say he needed to start afresh in a city where he had no memories of his wife or notoriety. Like Star City. What was the reasoning here?
I got a little excited at seeing Atom Smasher grow, like in the comic books, I won't lie. The "lead the villain into a trap and leave" plan was classic. But Atom Smasher's death seemed anti-climactic and a waste. It wasn't even that dramatic. What was the point?
Good job on not throwing away Star Labs and the secret future computer Gideon. That would've been stupid. How's it being funded now?
Jazzed to see Jay Garrick. Great ending scene. I can handwave Henry Allen's stupid excuse to lying about his real reasons to leave, Atom Smasher's weak death was the main disappointment. Everything else was decent setup.