Tip: Avoid "item babysitting". Do not force the player to drag P-Switches or springboards all around the level. This is not fun, nor does it make for interesting "puzzles".
If some rock mounds or trees or some other details are added to the OW's then it would help, but I think that your level designs should be good enough to still make this a good hack. I think a supporter bar is needed for this hack.
Your OW designs would suggest 6 worlds, not 4. Is it just me or have you changed it to 6 worlds?
Yeah when I said that I was planning on making this simply a 4 world hack but then I later added an ice area to world 2 so it ended up taking up two submaps and then I later decided to add a special world so now it uses 6 submaps instead of only 4 like I had originally planned.