All of the articles about levels in Yoshi's New Island, many levels from New Super Mario Bros. series (as an example, Waddlewing Warning!; others were taken care of) and Yoshi's Woolly World (Rollin' Down the River etc.), and some levels from Super Mario 3D World (Conkdor Canyon etc.) and Captain Toad (Multi-Vator Mayhem, Secret of the Golden Realm etc.). To a lesser extent, articles of levels from the Wario Land series, specifically those from Wario Land 2 onward. However, I've seen people actually giving the latter as optimal examples for how a level article should look like, and indeed they are concise and well-written, but they could really use more info. (In The Curious Factory, you can use paddle wheel-like mechanisms to climb up some sections, but the article doesn't make note of that.)
I think in most cases, the layout of a level is hard to describe, so writers resume to making really broad descriptions of what the level looks like. However, in the process, they sacrifice a lot of substance--in my view, a level article should reflect the experience one would have with the actual level, as much as possible. It's best then to write an overview of the level from the perspective of the playable character, giving instructions on what things the player should or is required to do step by step, rather than focusing on the physical appearance of the level.
Perhaps we could change this to a level article improvement project, as I agree that a lot of the Yoshi's Island pages in particular are poorly made. Honestly, something like the Super Mario Land 2 level articles are what in my opinion a level article should look like. I have been trying to improve the CTTT level articles which I hope to continue, although this is something that as a whole needs to be improved.