There have been many spectacular ideas on this... these are the ideas i liked the best
1. Custom Robes - Hooded, Anakin like, anything you damn well please
2. Custom Lightsaber Hilts - Curved, color
2.5 - I'd like to have custom color blades.. like make your own color by mixing colors or something
3. Different fighting stlyes (not needed, but would be awesome) - I think that it would be cool to see a ds player attack the other person with a lightsaber like Anakin's style. He murdered Dooku in form. In the book it even says that Obi-Wan and Anakin played with him, acting like they were weaker than they were. The style idea was a good one, but it should have way more effect on lightsaber combat. Like if you use a blaster bolt deflection form against a jedi, you will get killed. They will be faster than you/stronger than you etc. Also, Master Power Attack, and Flurry were cool, but k3 should either have more attacks, or combos. The take and give damage thing is cool, but for a Jedi, unrealistic. What Jedi will fight, take a break and let the other person attack, and then attack them again? I mean it's turn based combat, but you should be able to keep attacking, and with different attacks.
4. The idea about DS using LS powers and vice versa was good, but a Force user (jedi, sith, or neither) shouldn't be restricted to any side's power. I also don't think that powers should be inherently good or evil. If a Jedi has to kill someone, then why does it matter if they choke them with the Force or chops their head off? What Sith wouldn't use the Force to heal their wounds? I understand that there can be instances where people would think that choking someone or crushing them with the Force would be a more cruel method of killing than a lightsaber, but death is death. It's what you feel/your motives when you kill them that determines whether it's good or evil, not what method you use in killing them.
5.I like the idea of parties mixed. Like having Bastila, Mical, Mira, Mandalore, Carth, Jolee, and Juhani all in the same group. I wouldn't want to be the Exile or Revan again, but I'd like to meet up with them, and train with them in each of their ways. That would be awesome.
6. I also like the race ideas. Be a Twi'lek like Aayla Secura, or be a Devaronian like the character cut from K2. Color was an okay idea, but there should be more things like weight, height, face construction, and the classes should be more different. Like a Consular in a battle with a Guardian would have to use the Force to win the battle, and if the Consular used the lightsaber too much, they'd lose.
7. I like the day and night, requiring sleep idea. It makes more sense other than leaving and exiting the Ebon Hawk and it's always the same time. Also, I loved the weather idea. There should be a snow planet, and if you use master speed, you slip and fall and slide or something. If it's raining, similar things happen. If it's hot outside, have the character wipe sweat off their heads if they're idle, or in the middle of conversations. That brings me to my next points.
8. You should be able to pick your voice in the beginning of the game so that when you pick a dialogue option, you can hear your character say what you picked, gestures for how the statement would be said, emotion and things like that. Smiling, smirking, satisfaction, malcontent reactions when the person who talks to you says what they say back to what you said. Also, have a conversation opener. It's kind of weird how when you choose to talk to someone, they talk first. What do you do? Just stare at them until they talk?
9. Influence was a spectacular idea, but was done completely, totally and utterly wrong. I had a Dark Sided character and had all possible companions as Jedi. They were darksided too, but when I killed an innocent, i would LOSE influence with them. That makes no sense. If they follow you to the dark side then, their personalites, not just their bodies, should change as well. The DS corruption should change them entirely. I also think that you should have the choice to pretty much fall in love with members of your group and almost have a relationship. Maybe even someone getting mad if you try to have the 'love quest' with more than one person. It would require extreme influence, and choosing to break the code of the Jedi if you were one. Ape Siddious came up with the greatest idea ever about the trials thing. I think that your Master should be a required member of the group until you become a Knight. Also with influence, I'd like to see people leave your group if they don't agree with you, or you choose to leave them someplace.
10. I LOVE the long game idea. I would like to be able to go anywhere on a planet, and in the Jedi temples, sit and actually read knowledge they have of the Force.