Things I would like to see for KOTOR III:
Make the lighsabers more customizable, where you can choose all of the parts of the lightsaber, to make the inside and ouside more unique to each persons PC.
Make the PC more customizable, choose species, skin tone, hair color(If any), eye color, and choose their undergarments, everyones in KOTOR II looked the exact same.
Make the Jedi/Sith Robes have a hood that can be up over your head or down on your back.
Make the characters resemble whatever world they are on, if it is a desert make the clothes look sand worn, if they are on a planet where it is raining make the clothes look wet and slick the hair down (If any)
Make Full headed Helmets, like the Mandalorian helmets or the Ubese environment suit helmets.
Old Characters To Re-use: (Not necessarily a NPC but shows up to help or teach you something new)
Mira
Bao-Dur
Visas
Atton
Bastila
Mandalore(Canderous)
Revan
The Exile
For New Characters use: (NPC)
An Anzati Spy
An Iradonian Mercenary
A Chiss Pilot
A Twilek Thief
A Jedi Knight Corellian
A Force Sensitive (Yoda's Race)
A Sith Apprentice Bothan