This sounds like an interesting situation; I've never really looked at optimising Kinetic Combat before. I guess the place to start is to look at why you'd use KC in the first place, and work from there:
Firstly, and fairly importantly, you get to attack at a distance, which comes with the obvious benefits of survivability and flexibility; you don't need to worry about taking talents to aid your movement, as you can, for the most part, remain 'safe'. One way to optimise this is to really make sure you are out of harm's way while using KC; powers like Surge to get you onto high platforms, high stealth checks, that sort of thing. I note that confusingly, in the KC description, there's no mention of needing line of sight to maintain or use the power, just that you remain within 12sq. If you accept this, as a GM, then things like Smoke Grenades can provide extra defenses.
Secondly, with Improved KC (an obvious selection for someone specialising in it), you can wield three weapons, each of which provoke AoOs, so you can really get your money's worth with Combat Reflexes and a highish dex. Other things which play well with this are the Hold the Line talent (great for protecting you+other ranged combatants from melee charges), Demoralising Strike feat (plus other intimidate combo talents, if your player has Noble levels, great for getting more out of your AoOs that just damage).
Other things to note: KC doesn't specifically mention lightsabers, just one-handed melee weapons. While obviously, lightsabers are going to be the weapon of choice for melee, I noted a cool synergy with Force Disarm; if you Force Disarm somebodies weapon at range, and choose the option for it to fly into your hand, you can then use it with KC next round, which I thought was pretty funky, if not particularly powerful. Force Disarming people who are locked in melee combat with you at range seems good though, although action-intense.
The only weapon which qualifies that strikes me as particularly 'optimised' just beyond a basic saber is the oft-ridiculed Lightwhip; using the Threats of the Galaxy writeup, you can pin and trip people even without the feat (bypassing the restriction on KC, depending on how you view it?). I think a fair house-rule here would be to allow Cha rather than Str on the opposed roll
But I love the idea of tripping people over with KC'd lightwhips! This could really add the punch your player is looking for, power-wise. Don't forget that lightwhips also have reach, making all the AoO stuff above better as well!
Finally, KC obviously has the [Telekinetic] keyword, so looking for stuff that combos off that is a fairly easy optimisation; One that stood out for me was the Waveform talent from the Order of Shasa tradition, which could easily be ruled to work with KC; might require a bit of flexibility from you, the GM, if you're normally strict about buying talents from traditions. Mini-adventure time?
That's pretty much all I came up with. I like the idea of the Lightwhips most, can really provide some very solid battlefield control once you get Improved Kinetic Combat.