Here is my "short" list.
-Choose which character you play as Revan, Exile or Kreia's Son/Daughter
-Add even more saber colours in to the game.
-Add unique saber models into the game.
-Allow a wearable Revan mask you can get from Mandalore.
-Allow you to piece togther your lightsaber.
-Keep HK-47 as a party member.
-Allow you to play as Aliens e.g Twi'leks, Biths, Duros and Rodians
-Add extra more realistic saber soudns into the game.
-Add extra party member slots
-Allow who you want in your party and who you don't
-Add a multiplayer feature like JK
-Add a party puppet for every party member only at choice
-Add Atton as a party member
- Add The Exile or Darth Revan as the final boss.
-Make time manipulation a power you can learn from Kreia (ghost)
-Let you customize your head e.g hairstyles, eye colour, hair length, hair colour and skin colour.
-Age the main character gradually.
-Return Juhani or GOTO
-Bring back Malak
-Make the cheat console invisible
-Cut anythng from the game