There's a fair amount of thoughtful, creative levels in Mario Maker too, they're just harder to find. The level searching is definitely something I hope gets improved in Mario Maker 2.
Fair enough. I will say a full campaign creator would do wonders. The great thing about a classic 2D Mario (or any single-player campaign, really) is that you have new ideas, items, and layouts introduced at regular intervals. There's a feeling of forward progress, not just in terms of narrative but also mechanics. So far, it's been tricky to recreate that in Mario Maker.