This is a good start, all you have shown us so far is a palette change,
I am also working on a Zelda 3 Hack Tetra Prism, if all goes well I hope to be able to resume work on the project sometime in 2008.
I will of course need help with the project so keep working on your Zelda 3 Skills and I may consider adding you to my Zelda Hack Team.
You first need a lot more experience before you can jump any a huge project. Start small and work your way up.
Also it will probably help you if you first plan your levels out on paper first, play some of the other LttP hacks to gets some ideas.
http://www.romhacking.net/docs/PGTZ3E13.pdfHere is a link to the most comprehensive Hyrule Magic guide in Existence.
Good luck.