So how about that 14×14 promo...
I really don't like the promo for 14×14. If they decide to make Jack soulless and turn him into a villain just for shigs, I may well quit watching the show. I know this might not be the case (we've already had some slightly misleading promos this season - like Dean in the box actually being a dream sequence, for example), and we don't have the full context surrounding what happens in the promo... but I still don't like it, and I have a lot of really bad feelings about it, and I'll have to stew in those feelings for the next month until it airs and possibly after, so... yeah.
I adore Jack's character. I've loved him since his first full episode when he said Cas was his father. His sweetness, and sensitivity, and capacity for love and kindness in spite of everyone's expectations that he'd be as evil as Lucifer is what makes him so compelling to me. I love Jack probably as much as I love Cas, which is A WHOLE AWFUL LOT.
If Jack burns off the rest of his soul to use his powers, he will die - his soul is what powers the magic that's keeping his body from shutting down. And since his soul will be gone, there will be nothing left of him to ascend to Heaven when his body expires. He will be completely and utterly destroyed.
And all the sacrifices that were made to ensure his survival will have been in vain. Lily's sacrifice, Dean's sacrifice (remember, he said Yes to Michael to save Sam AND Jack), Cas' sacrifice, HIS MOTHER'S SACRIFICE. Not only will Cas will be relegated to in eternity in the Empty for Jack to use his powers only a few times, but he'll have broken his promise to Kelly in the worst possible way. Dean may or may not end up being tormented by Michael forever in the malak box, only for Jack to lose his soul and become as big or a bigger threat to the world than Michael. Kelly will never even have the chance to see her son again in Heaven under any circumstances, and if she ever found out what happened, she'd never forgive herself for letting Jack be resurrected using magic powered by his soul. Lily would have died bringing him back for nothing. Sam would be faced with failing to save yet another person he empathized with, someone he was always told wasn't worth the effort, someone he saw so much of himself in, from turning evil, the same way everyone expected Sam himself to become evil prior to the end of season 5.
I enjoy a good dose of Winchester Angst (TM) as much as the next fan, but seeing Jack lose his soul and turn PermaBad would break my heart in a way that I don't think I could forgive (and I almost quit watching when they fridged Charlie and Eileen, but stuck around anyway, so I feel like I've already given them a lot of leeway).
Jack has always been keenly aware of the sacrifices others have made for him, from the moment he was born. And we know he doesn't always feel worthy of them (as in 13×02, "Maybe I'm not worth all this."). But it's also not as though Jack doesn't know how loved he is - all his parental figures have always tried to make clear how much they love him, and how worthy he is of their sacrifices. For Jack to take that most sacred of sacrifices - that of a parent for their child - and just throw it away for short-term access to his powers... feels utterly wrong for his character, and is a violation of everything his family has done for him. I'm not opposed to experimenting a bit with his character, but not if it turns him into the kind of monster he's been terrified of becoming from day one.
(Also, the last 8 or 9 consecutive episodes have all made me cry, and I'm getting kind of angsted-out. Part of what I love about SPN is that NOT every single episode makes me want to lie down and die - they usually break up these long stretches of sad with a bit of levity, but they haven't really done a 'funny' episode since before Jack died. It's kind of emotionally exhausting, especially for someone like me who's hyper-empathetic and sensitive to emotions. STOP HURTING ME LIKE THIS, I NEED A BREAK ONCE IN A WHILE, GODDAMMIT. )