I think Arrow had the same problem in Season 2 for the same reason, with Ollie ping-ponging all over the place. The issue is that they don't want to let the show grow, and thus they can't let the character grow. It's less about 'what can we do to challenge Barry to grow on a personal level' than 'How can we make it so that Barry is struggling with the challenges we want.' Instead of exploring this huge universe in the comics they touch on it to try and bring us back into what they want: to re-do Season 1 of Flash.
The character in the Season 1 finale had grown enough to let his mother die in order to preserve the timeline. Somehow, after dealing with Earth 2, which gave him the same challenges in terms of a speedster trying to steal his speed, traitorous mentors, his mother's death, the melancholy of Harrison Wells and led him to be less mature and forget a lesson he's learned the hard way twice already.
All this for Flashpoint... except, it's not about Flashpoint. Flashpoint is about turning everything we've seen through the whole of the comics history upside down. But we just saw that on Earth 2, which serves the same purpose, but there's not really much of Earth 1, at least Flash's corner, to go off of to make Earth 2 worth exploring more than two episodes. Beyond that it was just fodder for Harry's storyline, which, mindbogglingly, was more important than developing Barry, to say nothing of new characters to expand the universe.
And so that's why I feel kinda betrayed, not just that they have turned Barry into a plot device, and not just that they aren't interested in the Flash mythos beyond using them to draw eyes to their favorite actors. I mean, if you have the cast of Prison Break and Spartacus and frikkin Mark Hammil lined up to play one of the top three rogues galleries in the history of comics, you do not, full stop, DO NOT sideline and bus them off to spinoffs in favor of an original character masquerading as a comics foe. And they set it up, with Cold being compelling as someone who can get in Barry's head, but they didn't really want to pay off Barry's archnemesis. Go fig.
And I think it's kind of unavoidable that Barry can't grow. If Barry grows then he gets better and you actually have to challenge him. Flash is already silly enough with things that bother Barry that shouldn't. The first episodes did okay, giving him challenges for his CSI mind, and physical obstacles like tornadoes and one man armies and gas that even a speedster can't just outrun. At some point though, they stopped thinking through these things and it became about Harrison Wells' development, and if Barry got clocked by a normal person, it was somehow 'okay', and I'm not sure that ever stopped. Because a Barry that grows no longer needs Harrison, Harry or any Earth 3 permutation that Flashpoint will assuredly set up. He outgrows even Joe after a certain point, not that they aren't still relevant, but they can't resume the roles in his life they did in Season 1, because Barry doesn't need that anymore. A Barry who is a fully functional CSI, who can be anywhere in the city in a moment, who can search the entire city in a matter of hours, and don't even get started on AugCog or anything like that, fageddaboutit.
So they have to keep Barry from growing, or else the show will change, and not just for a Flashpoint episode, but they'll have to leave things from S1 behind, and not based on how much they like the actors. Same thing happened to Arrow, and honestly the same thing on Heroes. They held characters whose storylines had ended and so their central characters never developed because they wanted the supporting cast to be the same forever, becaue they liked the actors. It was Season 4 before Heroes, or Arrow realized how badly they f'ed up and it was too late to salvage. It looks like Flash is headed the same direction. Expect to see yet another season where Barry learns to let go of his mother's death, for the third year in a row, where Tom Cavanaugh plays the gruff pseudo-mentor and Barry continues to not be with Iris, Joe continues to cameo with occasional and increasingly vague wisdom, Cisco is a funny wizard, Caitlin is a walldressing and the big bad hangs out at STAR Labs. Expect to see lots of one-episode easter eggs or one-episode flips on this concept, but in the end, this show cannot grow. It's too into itself.
I can't believe at one time I wanted to see this Flash in the movies.