I honestly couldn't care less who produces the the next rider series, I just hope the writing/directing is better than how it is right now.
I'm pretty sure a lot of the boring stuff in Wizard originates with the producer. Specifically, I think Utsunomiya has some rigidly formulaic and restrictive ideas about how a hero should be presented and why children would find the shows interesting. He could get away with this in Shinkenger and Gokaiger, where he was paired up with extremely talented veteran writers who clearly worked hard to justify the things that, in retrospect, Utsunomiya probably wanted. Tsuyoshi Kida on Wizard is either not capable of working within Utsunomiya's constraints, or simply lacks the talent to produce more than a journeyman's copy of better writers' work. I'm honestly not sure yet. I feel like I'd almost have to see Kida write for a different producer to figure it out.
But this sort of thing is what I mean about the producer's influence over a show being decisive. A lot of things people associate with writing/acting are actually probably going to originate with the producer. Like, if you think the guy who plays Haruto is bland... well, he got cast because that's what the producer obviously wanted. If you think Kosuke is annoying and one-note, well, the producer probably told the writer exactly what kind of character he wanted. This is why who the producer is really matters. Even if Takebe is paired up with, I dunno, the risen ghost of Noboru Sugimura, Takebe would still have the final say over what said ghost could actually get written.
I feel like Takebe is the kind of producer whose poor inputs (or lack thereof) magnifies the flaws of any writer working with her..
To play devil's advocate for a sec, I'll note that we've never seen Takebe be chief producer for a writer at their peak in the genre. She's always worked with people like Inoue and Kobayashi who are super-veterans who've written tokusatsu for fifteen or twenty years. So it's hard to say if Takebe brings out the worst in a writer, or if she's just guilty of not being able to get good work out of a burnt-out writer who's already running out of ideas. I guess what I'm trying to say is that I'm not sure if Kiva, OOO, or Go-Busters really would've been dramatically better in the hands of a different producer. More focused, perhaps, but the actual writing on those shows is probably as good as you were going to get from that particular writer at that particular time.
Takebe, like any producer, has her strong and weak points. Yes, she's flexible to the point of seeming spineless... on the other hand, she has a knack for zeroing in on what audiences like about a show, and trying to play that up. I think her Wizard would be a lot better than Utsunomiya's, for example, because she'd probably have started changing the planned plot based on what audiences actually liked. She would probably insist that White Wizard needs to be someone we've seen before, even if it didn't make a ton of sense, and I can't imagine her sticking with Gremlin as a major cornerstone of the plot the way Utsunomiya has. If anything, I think Takebe probably would've recognized how much people liked Phoenix and expanded his role accordingly.
Is W's second half AMAZING?
I would say W's second half was amazing, but I also thought the first half was pretty amazing. There's a command of tension, tone, and pacing in W that is absolutely rare in the Heisei Rider series. It's also a deliberately and intricately plotted series, in which virtually every two-part arc contributes something to advance one of the show's overall arcs. Character chemistry is carefully balanced, but the show also had the good sense to let the characters evolve with their performers.
That said, I think seeing W out of chronological sequence does the series a huge disservice. A lot of W's impact, much like Agito's, came from how utterly fresh and different it felt at the time. If you've already seen OOO and Fourze retread a lot of W's basic ideas, then you'll be wondering what the big deal is. Likewise, I've seen people go back to Agito from retread shows like Faiz and wonder what the big deal was, because it feels like something they've seen already.