In the first two DS games, Thomas mentions a Mineral Town farmer. Now who could that be? It's your pseudo gender character. Claire or Jill for Pete, and Pete for the girls.
Karen lacks her signature blonde bangs. Why exactly? Well, Karen with her blonde bangs is a direct descendant of the blonde Eve from SNES. In DS (Cute) it's that Karen's descendant, so the blond has probably been knocked out of her genes or isn't main like with the other, Eve is also the original Karen's grandmother. On top of that, DS (Cute) takes place about 100 years after A Wonderful Life and Friends of Mineral Town. Plenty of time to lose the blonde. Or the old Karen just dyed them, and the new Karen doesn't.
If the player views all Rival Events between the couples, they'll get married. Sounds fine enough, but if the player talks to them, various dialogues of the characters reveals that they are all to certain degrees unhappy in their marriage. Griffin and Muffy are not entirely sure that they rushed, even if Muffy is happy to not have ended up an old, unmarried maid; Lumina and Rock still bicker the entire time and Rock flirts with women; Marlin is a bit intimidated by Celia now, who seems to have become more like Vesta and Carter wonders if it was a good idea to get romantically involved with his assistant Flora. The only, actually happy rival marriage is that of Nami and Gustafa. By the way, it was you, the player bringing them together by viewing the scenes. You doomed them to unhappy marriages.
You know, the infamous Non Standard Game Over in DS in which you grow a 99 level poisonous mushroom and put it in the soup during the Harvest Festival so everyone in the village dies, including yourself? Forget-Me-Not-Valley is now a mysterious Ghost Town, and if discovered (by shall we say the Mineral Town residents), they will find skeletons or rottening corpses scattered across the beach.
One of the Non-Standard Game Overs ends with letting your dog attack Thomas and the credits roll after a horrifying fading into red sequence. Your character just let his dog bite Thomas into a gory mess.