One of the better easy hacks compared to what else I've played in Legacy with a strong SMB3 theme, although it doesn't have a broad variety of concepts, and it has a screen-scrolling pipe obsession. Levels are mostly short to medium length.
Some ideas seem utterly useless, such as the inclusion of any Yoshi, because there are screen-scrolling pipes every half-second to five secons in most levels, and most of the time that means losing Yoshi at that point. Yoshi is also not needed for anything he can do.
This hack has a few major issues: Coconut Isle 4 has a bug that corrupts the level visually, and it's easy to get stuck in the room with the keyhole since you can't re-enter the screen-scrolling pipe like you expect to be able to. There are numerous places that expect you to retain a Fire Flower (which is often provided but still losable) in order to pass, and the final level's camera position, even though it's an end of demo level, will result in your death should you enter it since the exit is below which gets calculated as a "pitfall death." Music did not work at all when I tried it but it did not crash the game.