Here is a way you could keep Kyle alive, but have a new hero.
Say Kyle does get a padawan and is sent on a mission. On that mission you play as Kyle with the padawan as an npc. Kyle gets injured on the mission by a dark jedi. Kyle then couldn't go on on the missions so his padawan has determined that he will finish the campain with a friend who is also a jedi. At one point his friend is killed by the dark jedi that injured Kyle. Thus adding a reason to go down the dark path. And like JK1 you can choose the path.
Kyle did kill Boba Fett. Fett didn't die at the Pit of Carkoon. The pit spit him out because of his manlorian armor. You killed Fett in Dark Forces.
Oh and Snake may be back in MGS3. If he does I would like to see how he survived the tanker.
Just because I don't know something doesn't mean I'm stupid. It means you failed to tell me.