OMG, this is my ideal hack except it's on Ruby >:O. Well, if it's Fire Red style I like it. :D
This is probably the second best G/S/C remake I've ever seen. :3 Don't kill me, I liek Shiny Gold (:
I have some advice for you. Firstly, I wouldn't recomment using those custom tiles from Zel, soley on the fact that they don't match the other tiles and don't lookk nice in those palettes.
Secondly, your mapping. Try and use the other variety of Fire Red grass a little more. :3
And thirdly, Please change some of the D/N palettes, since they look a little weird to me.
Apart from that, good luck my friend!