I have nothing against the idea of a lightsaber being deadly. I think that's kind of how it should be; many posters above have pointed out the lethality we've seen in established media that lightsabers have. Usually, it's one strike and you're dead. Fighting a Jedi or a Sith /should/ be A Thing. When that mysterious stranger shows up and pulls out a lightsaber, your players *should* sit up and go 'Oh, ****!'
My only concern is that when the third book comes out, it'll pretty much invalidate player choice. This is the real issue with the Wizard vs. Fighter thing that's so hotly contested about D&D. Why would you play a character that is made pretty much pointless by someone else's choice? If your Jedi can kill things way easier than your Bounty Hunter, and then if he can also use Force powers to solve any other problems that exist better than people who have to specialize and give up everything else just to be good at their one thing, then… what's the point of playing anything but a Jedi?
I'm not saying it will happen like that, just that it's a concern. It's also a hard thing to balance with what I said in the first paragraph. Jedi and Sith should be lethal, but balanced in such a way that it doesn't make playing anything but a Jedi seem ridiculous.