WeightWatchers is really working for Mario, eh? (Even given the perspective, he's a lot skinnier than I remember him but I think this is a canonical transformation given official art.) Your RHDN pal did a nice job on that artwork.

I'm impressed by the level concepts. The balloon level is in constant motion; it's practically a living level. While your levels are eye-popping, this one especially stands out. I also really like the foggy mushroom jungle one, the ruin with the SMAS SMB1 hills, and that silhouette level looks like the African savannah. You've got good taste in tilesets. First OW map is very bright and full of variety and I like the depth and darkness in the second map. Everything around a level dot seems to suggest the setting of the level you are entering. The underwater level does look a bit drab. Is it intentionally murky? It's not bad but everything else around it is just so colorful that I'm wondering why even though it's deep water it's very grayish.

I think it's cool you put in transformations to gather hidden stuff and the way you handled it reminds me of how it's done in Yoshi's Island: the reward is geared on the proper use of that transformation and little is doable to bypass that need.

Your gameplay seems frantic with action seemingly at every jump if the poison forest and water temple are anything to go by. I see those water spouts could drive a potential profit for the swear jar. Are you aiming for a "Hard" difficulty? It's brimming with ideas and you have a lot of different gameplay mechanics. It looks like one of the fresher challenging hacks I've seen lately.

Since Mario has a persistent partner and you have an ASM guy, consider releasing an "Omochao Edition" of this hack before you submit the real thing.