His ending in IV: he leaves home to go and fight, leaving a note to his Mama, promising to come back "when I won't be an embarrassment for you anymore". The ending shows that he'd sent a letter to her saying he was in Hong Kong, prompting Samantha to fly outto him.
"People still stare at me sometimes, but I don't let it get to me. It's okay to make mistakes once in a while. As long as I get to spend time with my Mama, everything will be just fine."
His ending in Super is a down-right Happy Ending for him.
"I know it seems that evil is a gaping void in this world that can never truly be vanquished. But I keep my faith. Because the joy in mankind's heart is also endless."
Sakura's rival battle with Ryu in IV, between Ryu acknowledging her as a capable fighter and Sakura's theme playing throughout, it's a wonderful experience.
Her ending, too. Specially when she's jogging underneath a local bridge with her Akita dog... and she sees Ryu walking towards her.
In the Udon Street Fighter IV comic, El Fuerte and Rufus end up on a Ninja Warrior-like show along with Sakura and Dan. Sakura talks with Fuerte and finds out that he's a big fan of Rainbow Mika. When Crimson Viper shows up to kidnap Sakura, Fuerte leaps to her defense. A few months after the incedent, Sakura and her family show up at his restaurant in Mexico... and bring Mika along with them.
Sagat's SSF 4 ending, where he meets up with a group of Thai childrenand shows them kindness. It's really adorable to see the big-ass Sagat holding a little girl's hand as they walk peacefully through the rice fields with another kid and the local elder. Then it's subverted when we see it from Adon's POV in his own ending sequence: while the scene is still a sweet one for the viewers and Sagat himself, Adon is FAR more cynical and sees it as the proof that Sagat has grown way too soft.