1-2. Limestone Pie, the flinty and foul-tempered mare that runs the Pie Rock Farm, harbors a dark secret: she's never had a boyfriend, and she very, very much wants a romantic relationship. She's almost 27 for Celestia's sake, but she's got a farm to run. Pinkie Pie, being the nosy intrusive intuitive sister she is, offered to help take over the rock farm for the day so Limestone could have a day off and go have some fun (the results of such…is a different story). Pinkie discovers a Daring Do book underneath Limestone's bed, so she asks Rainbow Dash to take her to the annual Daring Do convention for her day off.
At first, Rainbow has to practically drag the reluctant farm mare to the convention. Eventually, they bond over their brash personalities, and Limestone actually starts to kinda, sorta….have fun. Suddenly, they run into an old friend of Rainbow's — a pudgy stallion with some…wow…pretty intense blue eyes. His voice is annoyingly nasally and he acts like he knows freaking everything…and suddenly Limestone feels weirdly shaky.
Rainbow (having a bit more experience than Limestone, already engaged to a certain Wonderbolt) recognizes the obvious symptoms of a crush. She assumes the role of "Super Totally Awesome Wingpony." That story is a bit of a longer one, in which we'll get to later…
(I don't even know where the inspiration for this ship came from. I just love the thought of these two constantly snarking at one another then making out passionately. plus i wanted to give patton pony a gf )
3. pretty much just see here. Their kid will actually be a main character in my Athenaverse (MLP next gen like there's not already a million of these)
4. Of course, an old favorite. I think mellow Soarin would bring out a softer, calmer side of Rainbow. Not that she'd ever let anypony else know.
5. Applejack eventually got fed up with Trenderhoof's laments about never finding love and destined to be a lonely hermit for the rest of his life. While he didn't further pursue the farm mare, it seemed he made a hit on almost every mare in Ponyville. Most of its residents were hardworking individuals, a trait Trend was obviously very attracted to.
When Rarity received a letter from Coco Pommel, mentioning briefly within that she too wishes for romance, Applejack pounced on the opportunity like no one's business. She couldn't stand Trend's whining any longer. So she throws these two together on a blind date, and the rest is simply history. Trend finds Coco criminally cute (while having an utterly fantastic taste in fashion). Coco just melts at her boyfriend's impromptu poems and sentiments. Applejack is relieved.