I actually just spoke about this process in depth on DisneyLorcana.com, but to summarize: The Set Lead Art Director for each set is responsible for coming up with the artistic vision for the Enchanted cards
Sacrificing artifacts benefits us numerous ways, such as reanimating things with Vat of Rebirth, making mana with Slagstone Refinery, making servo tokens with Sly Requisitioner, and draining our opponents to death with Marionette Master
That token gets exiled at the start of the next end step, but it is around long enough for you to do some shenanigans with it
I'd estimate that this strategy leads you to the right decision approximately 90% of the time
Im surprised this doesnt see more play, but in a deck where you want to leave your mana up its a nice backup ability
They remain separate objects in all zones