Any scene showing the five Bronze boys relaxing and doing things normal people do (eating, sleeping, exercising, playing guitar, playing soccer etc), mostly in early episodes of the Sanctuary chapter.
Also the Rousing Speech that Hyoga gives to the poisoned and injured Shiryu and Seiya in the Temple of Scorpio, to give them their spirits back after Shun's nearly Heroic Sacrifice.
The anime-only scene where Ikki thanks little Helen for her support and carries her home in his arms.
Speaking of Ikki, the chapter where we find out he's Back from the Dead includes a sweet scene where he wipes away Shun's Tender Tears and then is joined by all the other Saints as well as Saori, who are all crying happily.
Every single time that Seiya and Co. are able to defeat the villains (from the television series and the movies) by The Power of Friendship.