What a interesting topic!I always like to make up little headcanons for my ponies. Roseluck is one of my favorite ponies so I've made up tons of little stories for her.Here are some little headcanons I've made for my ponies.
Roseluck, or Rosie as some of the ponies call her loves to plant roses. Her motto,you can never have to many roses.She was born in Fillypool Enghoof some time in the 1940's and after being orphaned at a very young age ran off to find her ture calling in Ponyville Equstria in her teens. She owns a floral shop and the other ponies notice her Fillypool accent.
Minty was born on St.Patricks day in the late 1940s and is Ponyville's offical greeter and a very friendly likeable pony. She just wants every pony to be happy, jut like she is. She owns a sweets cart but loves to make herbs and has a secert collection of herbs.
And lastly Lemon Hearts is the daughter of the two richest people in Ponyville, or the richest couple in the 1950's when all this takes place. She was also born in the 1940s. Since she's kinda high maintence some ponies [like Roseluck] consider her a snob, but Minty says she's really sweet once she warms up to you.
Well thats all for now. I'll add more headcanons later.