I voted for all the "marry" options, the guard options, not bothering mane 6 and princesses, spending the years for research, helping ponyville, and dangerous task in everfree forest.
I would not swear an oath to anyone simply because that lasts forever (or at least as long as my mortal life). And I wouldn't mind not bothering the mane 6 and whatnot cause that would get me a chance to check everything and everypony else out. Wouldn't mind at all with the marrying trixie thing, I have an analysis that most of her ego is just an act and her real self is hidden so it would be fun (and frustrating at times) to try to get past the barriers and get to know Trixie, not her stage persona.