I get that it seems like the first paragraph of "concept" seems like it's been established as a boilerplate for Pokemon-related text, but it's just not a great way of starting off the entry. It starts off talking about fictional species of Pokemon without the context of the world in which it takes place, it manages to get a major factual error wrong (the first video games were Red and Green in Japan, not Red and Blue, and conflicts with the lead), and then re-explains (better, in that it expressly clarifies they're animals) what Pokemon are again in the third sentence.
In a similar vein, the entire article needs a passthrough doublechecking if things are being introduced in a logical way. Right now, for example, the Detective Pikachu film gets name-dropped in the seventh paragraph but not introduced or wikilinked until the following. Likewise, the article section on concept and design follows all this background info until it hits the fifth paragraph, which stops to explain in-universe gameplay and appearance elements that don't directly relate to the design; it feels like you'd be much better off explaining some of this in an Overview section before going into the background design info, because it's a really weird place to try and backfill context if you know nothing about Pikachu. We learn about Ash Ketchum in the video game appearances section but he's not actually given any context until the following anime section, et al.
Nishida stated that she was fond of squirrels at the time of Pikachu's conception, and so designed several elements of Pikachu to resemble squirrels. She stated that its tail was chosen because she liked squirrel tails, with the tail being shaped like a lightning bolt due to wanting a lightning motif in Pikachu's design. Pikachu's cheek pouches were added to reference how squirrels stored food in their cheeks, making Pikachu do the same with electricity. Satoshi Tajiri named the creature, giving it its mouse-like qualities. This is weirdly long-winded to explain she adopted traits of squirrels into the design, and Tajiri's naming giving "it" mouse-like qualities sounds like talking about the design, when you're in fact only talking about the name? Also who is Tajiri, and why does the article doubt his expertise on Japanese and add the "according to him" bit?
"This suggestion was scrapped"—"scrapping" a suggestion seems like the wrong word. That would imply they actually did work implementing it rather than just ignoring it.
In Pokémon Sword and Shield, Pikachu gained access to a special Gigantamax form,[51] which is based off of Pikachu's older, chubbier design.[52] Redundant with design section that already had this info.
Ash's Pikachu is voiced by Ikue Ōtani in all versions of the anime. Ditto.
The entire Detective Pikachu section seems like it'd be better off slimmed down and put in the section on the character's appearance. As it is, it's both not about the overall character, and also in between two paragraphs on voice acting that seem far more germane together.
I'm not sure what the line between merchandise and appearances is, but Pikachu appearing in the trading card game feels like the former.
The level of detail on the Pikachu floats in the Macy's Day Parade really feels undue. The important thing is it's a float, not when specific ones were retired or Introduced.
The big sticking point for me is the Legacy section. It's not organized well, and generally feels like a grab-bag of factoids loosely strung together. Stuff like the Hong Kong naming change really isn't about Pikachu at all.
The cultural impact is full of stuff that doesn't really demonstrate a cultural impact. That individuals liked Pikachu enough to name something in their field or dress up in protests is tenuously connected to cultural impact.
References:
A bunch of references are missing fields, for example website or author information; some are wikilinked, some aren't, some are capitalized or feature the TLD, others don't.
Others use the wrong templates, for example this ref (as of writing ref. 125) uses a cite web template when it's a journal entry and should be formatted using ((cite journal)) instead.
Considering Pikachu is such a big name, I'd expect to see some more in-depth sourcing. There's no shortage of books that discuss Pokemon's impact; do they not talk about Pikachu?
Media:
The fair use content in the article needs some work. File:Pokémon Pikachu art.png has a reasonable fair use claim as demonstrating what the most enduring representation of the character is, but File:Pikachu artwork for Pokémon Red and Blue.webp is fundamentally "Pikachu but pudgier" and doesn't have a strong fair use claim when you need to argue the article is significantly worse off without it. Detective Pikachu is a small part of the article (and I'd argue could be even smaller,) and hence File:Detective Pikachu Movie Development.webp doesn't seem critical, either. File:Pokémon episode 1 screenshot.png is likewise another purely illustrative usage.
