I think regardless of which lightsaber is used in the scene, having Luke appear as a force projection is more powerful, because it was the only way he could live up to his legend. He never could have faced down the entire First Order, as he said earlier, but he could outwit them with his cunning. This scene resonated very strongly for me (it’s actually one of my favorite scenes of the entire saga). The cinematography, music, and dialogue (“The rebellion is reborn today”) all reinforced Luke’s legendary status.

I am interested in seeing Ivan’s extended fight, but it’s more out of curiosity to see if he can pull it off. Storywise, however, it turns the scene into another boss battle. It’s also illogical, because Kylo-Ren decides to fight Luke by himself despite having his whole army behind him (assuming Ivan is cutting out all of the walkers firing at Luke).