Idk. I have already spent a lot on this game ( bought both Game stop Limited Edition and The Coarse Edition) BUT at the same time, having all of the content on the disc is really convenient. If something were to happen to my PS4, well I can just pop the disc in and don't have to worry about downloading all the extra crap again, plus if a friend wants me to come over and play the game and he doesn't have it, I can just take the XL over and have all content and ready to go as soon as the game goes in, not limited to the base roster.
I guess the deciding factor is going to be if trophies and krypt carry over or if I have to platinum MKXL and unlock it's entire krypt too lol if it carries over I might buy it and retire my og copy, but if it doesn't I might skip out, I just don't think I have it in me to unlock the entire krypt again and get all the trophies again too lol I just don't feel like it. Same with all the online skins, I don't fee like unlocking them again, and the mobile skins I only got because of a glitch, so ill me missing out on those too unless they are inlcuded.