Oh yeah thats right in TES you have to carry the object around... but... the problem still arises that you are invincible (a huge, huge problem) to everything besides bandits who can pickpocket you if you are really that stupid to let that happen, and then you walk into some city and then suddenly you drop dead because someone pickpocketed you.
I'm unfamiliar with that mod however so they may have fixed these problems but I'm still not convinced. I say leave it as a mod and keep it out of vanilla due to balancing issues.
The soul/item thing is temporary. You have to keep it for only a few days.
I have no delusions that this will make it into Skyrim, obviously it's too late to make suggestions. I just wanted to bring it up and see what other players thought.