Zelda 1 and Zelda 2 desperately need remakes because they're so hard to get into. I'm not talking about the difficulty or graphics; I'm talking about how they don't explain anything and how a guide is pretty much required to beat them without tedious hours of trial and error. They don't need tutorials or anything, just take out the many cryptic puzzles that require a guide, make the old cave people and villagers say helpful things, and stuff like that so that people can enjoy the game without having to follow a guide religiously.
Four Swords Adventures would also be an amazing remake for Wii U, extra players could use 3DSs. A completely new Four Swords game like this would be even better.
I believe those are the only Zelda games that still have a reason to be remade because:
LttP, OoT, MM, WW, FS: Already remade
LA, OoA, OoS, MC: Perfectly fine on Virtual Console
TP, PH, ST, SS, ALBW: Still fairly new and can be played on 3DS/WiiU