Okay, this is going to be long, but here are some reasons why Spike deserves the Shashu"¦.
- Spike wanted his soul, he wasn't cursed. And no, not just for Buffy. Because he knew it was the right thing to do. He wanted to become a better man. Angel was cursed, and let himself lose his soul TWICE. Then he accepted to be Twilight and kill many people and Slayers.
- Spike gave up his life to save the world. Angel, as opposed to him, tried to destroy the world.
- Spike tried much harder to fight the good fight WITHOUT knowing about the Shanshu.
- Spike has become a good man BEFORE he regained his soul, he really tried, even though it was hard and painful to him, even though everybody hated him. He helped even though he didn't have to, even when Buffy was gone.
- Spike went through hell to get his soul, so he really really REALLY wanted to be a good man (no, it wasn't just because of Buffy! Read above).
- Spike wants it more, otherwise he wouldn't have won the fight with Angel. For the first time Spike beat him. And Angel admitted that.
- Angel had chances to live as a human being. He CHOOSE to give that up.
- Angel murdered people-humans even when he had a soul (i.e. Wolfram&Hart gang , (tried) killing Wesley, for example).
- Spike is the most humany vampire ever, he's as close as a vampire could get to being a good vampire, he's not a true evil. Even when he was "evil" he really cared for the ones he loved (Dru), he had human feelings that weren't brought to him with a soul.
- When he did bad things, he asked Buffy to kill him, he was very aware of the bad things he's done and wanted to keep the world safe by finishing himself off. When Angel got his soul, he didn't try killing himself or even redeem himself. Not in the beginning. In the beginning he was wandered around the world and hate rats. He didn't move himself to help and be a good man until he saw Buffy. He didn't have a true desire to redeem himself and fight the good fight, he just brood.
- Spike did good things even before the soul. And he didn't wait for anything to come across him (like Whistler to Angel), to "magically" make him get off of his butt and help to save the world.
- Even if Spike loses his soul, he wouldn't be bad. He'd still be a good vampire, he'd still love Buffy, he'd still try to make things better. Which means he's a true fighter, a true lover, a true friend, a true hero, a true good man.
- Spike would do ANYTHNG for the ones he loves, even die for them, even a thousand times. Even if he'd be tortured (like by Glory).
- Angel(s) is the one who made Spike (William) a monster. William as a vampire wasn't evil at first. Angel(s) made him do all those stuff, he is the true evil.
- Angel was the worst (evilest) vampire in the history, and he still is without the soul. And no one can change that past (not to mention that he killed many when he did have a soul). Yes, Spike has killed also, but besides the fact that he learned that from Angel, he turned himself good and choose the right path "“ the good side, he CHOOSE to be good. He didn't have to, no one made him, he wanted that with all of his heart. (no, not just for Buffy, and it's proven when he kept fighting along with the scoobies even after Buffy's death).
- Spike had to fight much harder to get into the good crown, to be trusted, even after he regained his soul. For Angel, it was enough just having a soul. But Spike had to work harder to be trusted without a soul. And he did a great job at that. And when he got his soul, in season 7, he was the only one Buffy trusted, because she saw his journey, she saw he is real and worthy of her trust.
- Speaking of journey, Spike's was much harder and turned out much better (in my opinion). Because he didn't have a soul and had to work it out somehow.
- Spike, even without a soul has conscience, he knows when he's done something wrong and he tries to fix it. Vampire can't have conscience because they don't have a soul, they don't care, they don't sorry. But he does. So he is a good man, even before he turned good (for example, when he snaps on Dru, he's sorry, and when he slept with Anya he tells Buffy he's sorry).
- He's succeeded climbing into Buffy's heart after being her nemesis. When he wants something that much, he gets it. He knows that hard work is hard work, and that doesn't stop him. Buffy told him to get lost a lot of times, but he stayed, because he loved her. She was mean to him, yet he kept loving her, kept caring for her, and didn't get mad and killed her.
- In the end, even though Buffy finally said she loved him, he decided to stay and die for her and for the world. He choose life of his love instead of his own. He didn't think about himself.
- Which proves that he's really changed. He's changed so much, and didn't just wait for this to happen, he worked for it. And more importantly, he WANTED to change. He CHOOSE to change.
-Angel might have done it for longer and more (saving the world) but he's been good for longer time! If Spike was good before, he was the one to do those.
I could probably continue, but I'll free you from that. I know there are things you might disagree with, but these are my reasons and how I see it. Just so you see that there are reasons, and it's not just out of my love for Spike.
And I still think that the argument about it being Angel's show is not a reason for him to be deserving. It's not deserving, it's just the world outside the show - it's outside the show, not in the show, so I really can't count that as a deserving reason.