Well, I have a whole team of OCs, so...
Pathfinder, Sojourner, Stargazer:
These three pretty much work and live in the Derbyshire Academy of Pony History; and this is possible because Sojourner & Pathfinder own the museum in a partnership AND there is a lack of residence in the small town of Derbyshire. XD
Sojourner (earth) is an archeologist and the main curator of the museum, while Pathfinder (unicorn) specializes in mapping & cartography. I'm still brainstroming over Stargazer (crystal), BUT I'm having her as an astronomer specializing in how ancient cultures viewed the stars.
Corsair, Spirit, Opportunity:
Corsair (pegasus) is the leader of a band of mercenaries called the WingHearts. Their main purpose is to help out anyone & everyone in the land...for a profit. I'm still working on some of his finer details, but he will take residence in the wild, more than likely.
The twins Spirit & Opportunity (pegasus) were originally with my museum characters, but I think they may be more interesting with the mercenaries. Right now, I don't have much with them other than that they love tinkering with gadgets, though they can serve as mechanics; I guess.
Professor Black Hole:
He's my only antagonist pony. An elderly pony based off of a cartoon villain (Professor Screw Eyes, cookie to the one who remembers him), he was an earth pony with magical properties thanks to the unicorn horn lodged in his eye.
I don't know if I would ever try him out for EqE, BUT he would likely require some changes from that. XD