They're all good, but the first two are hardly platformers. Limbo has platforming elements, but I'd say it's about the story first, with puzzles being a distant second and platforming really only existing to serve the first two. It's a great game, don't get me wrong but the most impressive things are the atmosphere and set pieces...if you want a gameplay challenge it's not what your looking for.

Little nightmares is similar, still very story and atmosphere driven with impressive set pieces...but I think the puzzles and stealth/timing makes for better gameplay. Again, not really a platformer (don't think it even has a jump button), but the gameplay it does have is more challenging than just being a vessel for the story.

Finally, Leo's fortune is the only true platformer and definitely the one focused most on gameplay. I don't even remember the story...though I do think it gives you one in the form of skipable cutscenes. Really though, the core of the game is platforming with mild puzzle elements. It also has the most replayability because the physics allow you to build a lot of momentum if you have good timing, so you can play the same level again and keep getting better scores.