Gridman really did stick the landing. I feel like the modern Gridman design is more appealing than the original, but I understand why they went back to the original for the final battle. It's nostalgic, it represents Gridman's completion, and the new design would be absurdly difficult to animate an entire fight scene around at Trigger's usual breakneck speed and tv anime budget.
I do kind of wish they would stop being big chickens about girls though. It did ~sort of~ confirm Rikka's feelings for Akane, but in a very careful, safe way that could still be interpreted as friends. Kengo is just a smidgen braver, but he's also in charge of fanservice and at least partially responsible for Rikka and Akane becoming a thirst meme, so, idk. It's become fairly common to include yuri bait in fanservice materials that are not part of the actual text of the show, which is, eh, i don't like it at least.
I don't really like dumping Yuta's feelings out there when they just aren't super relevant? Like they can't just ignore them because they brought it up in other episodes and it would feel bad to just forget about it, but, because they're toeing the line between friendship and romance with Akane and Rikka, it feels like it's sort of infringing on the whole... akane/rikka thing, if that makes sense? Especially since it's a same sex relationship and Trigger's record on those is, like, KLK did it pretty well with Ryuko/Mako, but they sort of repeatedly bungled it after that, at least from the perspective of representation.
I think it's worth noting that things can work in isolation while still being kind of an icky trend, so it's more complicated than just "thing bad."