Sincere Scholar is the head marestress we all wish we had. The knowledge and sheer wisdom she possesses in all areas could give Queen Galaxia a run for her bits.  
She takes her classes and running the Equestrian education department very seriously. The Cheerilee and Ms Harswhinny componants of her will stop at nothing to ensure her students nab the best grades possible and blossom into their utmost potential whilst the sheer showmanship of Trixie makes sure they have fun doing it, to the point where it doesn’t even feel like work with creative and engaging lesson structures. Then of course you have that leading authority and a fair but firm hoof of Spitfire which comes in handy when the students even dare to misbehave as well as making sure her voice is heard in teacher meetings (oh and it comes in handy for some hooves on wonderbolt lectures)