ArghMyToast
This game has more mission diversity, more COs, new Super CO Powers, and is overall an improvement over the first game in just about every way other than the fact that the AI still cheats in Fog of War (Edit: this is fixed in the Switch remake, so I would recommend that version). I personally liked the later games better, but if you want the most “pure” form of Advance Wars, this is it.
2001
My biggest complaints with this game were the lack of diversity in campaign missions, and the fact that the AI cheats in Fog of War maps (Edit: this is fixed in the Switch remake, so I would recommend that version). Still not a bad game by any means, just know that the later games in the series are much better.
2016
2019
2009