Star Wars Episode VII trailer released

[Lemonray]

As someone who has experience wielding actual swords and mock lightsabers I can say that the cruciform saber-hilt is a bad idea.
If you were to make use of extra lightsaber blades for a guard your safest possible bet would be something like this;

Spoiler

Then again, having a guard that can be made to cut against you is a terrible idea for any weapon since the guard will end up touching you. Remember that the main point of a guard is to keep dangerous parts of other objects away from your hand and body.

Of course there's no reason a guard couldn't be fabricated from one of the lightsaber resistant materials found in the Star Wars universe.