Of course from the moment they decided to include MagnaGuards they should have known that problems would be spawned. Giving them a blaster was the obvious choice, but that completely mess the unit's relation to the movie. Why they didn't include a cloak is beyond my understanding; they really look stupid without one.
The possible solution I see is to give them both a staff and a blaster of some sorts. I would let them keep the bulldog thingy, scrap the launcher and replace it with a staff. To make them "viable", I'd buff their health a little (kind of like a wookie) and make it so that staves do more damage to Jedi heroes.
~Dark Cupcake of the Sith