sure you could do it by CG'ing in some new digital actors to make it more dynamic but think about it.
kenobi's old in ANH and vader is all machine so both of them are well past it. then you've got luke who's had basically no saber training from kenobi, and you don't see yoda giving him any either so I think it fits that at this point, everyones rubbish with lightsabers.