As far as I know, g_saberrealisticcombat 1 doesn't make the game any less ballanced. Your 'saber still does the same ammount of damage it does without the cheat. The only difference is that when an enemy's hitpoints are drained to zero, whatever your lightsaber touches, it dismembers. With 1 activated, your nuetral blade DOESN'T HURT FRIENDLY NPCS. Try it. Walk into friendlies with your blade. It'll sort of look like you're hurting them, but their hitpoints don't drain.
g_saberrealisticcombat 3 is the one-hit-kill that unbalances the game. And nuetral blades kill everyone - including friendlies.