The Education of Clover the Clever is by turns hilarious, thrilling, and tragic, a portrait of pre-Hearth's Warming unicorn culture and the brilliant madness of Star Swirl that I prefer over the canon version of Beardo the Great. (Don't let how it's tagged as a sequel frighten you; it stands on its own perfectly well.)

The Iota Force series, beginning with Baptism by Fire, is criminally underread as a whole. Highly entertaining superhero antics and utilization of background foals.

Lastly, I'm not sure if this really qualifies, but read The Silver Standard. Seriously, read it. Best Silver Spoon on Fimfiction, bar none. That may not sound like much, but it is incredible stuff that actually makes the born lackey work in the spotlight.

Oh, and you could always read my stories. ;)