Given my natural aversion to *usted* in Spanish and *vous* in French, I'm starting to think that out of consistency I should adopt the Quaker *thou* in English.

Unfortunately it's a tough bind because the Quakers originally adopted it out of a democratizing instinct — *thou* was the familiar second person and *you* the formal — but in the modern era it sounds archaic, making it sound MORE formal than *you*.

Also it's a very weird thinking to do.