I didn't said that Shujinko would be dead, dammit!
Imagine a more deeper aproach to his character, and a more specified and structural storyline for him (I mean taking out the idiotic episodes in his konquest mode-such as retrieving the dentist, and so on, and so on, and so on...)
With Liu Kang gone (Oh no, Raidens blasting them with a thunderbolt is not an explanation, ergo he remains dead!!!) only the classical MK characters would remain (Kung Lao, Sonya Blade, and Cage with Jax-who should retire from MK games already-altough I like them) Kangs place could be filled with Shujinko, while the overall leader and master advisor for the party would be Bo' Rai Cho.
I don't think that the party would accept Raiden back with his current behavior! Curricullum: Shujinko shall/should remain!
Again, I didn't describe an undead Shujinko, but a -viciously scarred on the torso- more dramatic character! Thank You!

You're right, just "old" will do. He looks "wise" but he isn't... it's true