As usual for me, I only ever remember to come back to this forum when I see Pokémon news exciting enough to make me want to go somewhere and just talk for a bit about how I feel about them, lol.
Anyways, really excited Legend Arceus not necessarily for how good it looks (I think it looks really good), but for just how ambitious it feels within Pokémon's mainline series (I know this is kinda more of a side-game, but... close enough).
While I'm not AT ALL the kind to think that "Game Freak is lazy, they don't care about their games!!", I do kind of think that their Pokémon titles have kind of been in a weird place for a really long time. Red & Blue were the first games and have set the first standard for the series so there isn't much to talk about those in this regard, but Gold & Silver really stand out compared to other Pokémon games, because they were the only ones to exist within the context of "Pokémon as an already existing series, but one that only has one game", which means that they only had to obey to the standards and expectations that come from this one other game, and no other. This ended up making it more of a direct sequel to Red & Blue specifically than just another set of Pokémon games.
Then, Ruby & Sapphire had to create yet another standard, one that introduced a brand new region instead of building on top of an existing one, so I'd say these are still very important and ambitous games within the context of their releases. Every other Pokémon game after that though, have simply followed the standards introduced by Gen 3 instead of trying to create their own. Not to say that these are bad games, on the contrary, I prefer most of them over the first 3 Gens actually, just in terms of their quality. But these games don't feel ambitious is what I mean, it feels like they've always had to obey to expectations stablished by the series' history.
That's why Legend Arceus feels so interesting, it feels like it's finally breaking away from this and trying to do something interesting with the series' basic concepts instead of building on top of an already existing structure. It's a game that feels truly ambitious in a way that the series hasn't seen in quite a while. Even if it doesn't turn out to be quite as good as we all expect it to be (I hope this isn't the case, of course), it might still end up being a very respectable game when compared to what the series had before.