It just sound like you are missing the textures for the mystic elf. Probably Rens? If there is an esp file then it points to where it needs to go to get textures. So whatever happend to cause your charater to go invisible needs to be found. The save are only that, the state of the game. You need the actual files in the data folder. You can look at your save file in wry bash (in the saves tab) to see things about it.
You can go back on saves until you find one that works with the files you have installed but it will not find what you are missing for after the problem started.
However, the save will show all the esp files that it used thus at least showing what mods were installed but not mods that only had textures. (which looks like it may be the problem). Look at you old backup up oblivion folder. in the obmm directory there is the mods directory where all the omods are. Perhaps you are missing an omod of textures?
You can go back on saves until you find one that works with the files you have installed but it will not find what you are missing for after the problem started.
However, the save will show all the esp files that it used thus at least showing what mods were installed but not mods that only had textures. (which looks like it may be the problem). Look at you old backup up oblivion folder. in the obmm directory there is the mods directory where all the omods are. Perhaps you are missing an omod of textures?
I found a Omod with retextures of the HGEC body, I tried install that, but didn't work. I then found Beautyfull People, which I think that save had, I also saw some Ren files within them, so I just added the mod, also added a texture replacer for the Mystic Elf race, but I think that's basicaly for the face, and that didn't work either. Also tried reinstalling HGEC and the HGEC retexture with no results.