I have a theory about that...It seems you're running afoul of George Lucas' inconsistencies in storytelling. He tends to 'half-do' things. Like Queen Amidala. She is a child queen, but elected. This is a very odd contradiction that is the result of Lucas wanting to present a peaceful and just monarchy, with a queen who was capable of falling in love with the young Anakin. The details didn't really matter, even if it doesn't make sense.Evil? Here and there, but mixed with good and all in the grey area.
Suppose there' a high school applied Ethics/debate course with a competition for actual elected positions, with the highest seat being "Queen/King for a year." Amadala hapened to win it in time for the trade federation blocade- her responce got her a permanant goverment position as Senator (as long as the chain of high schol aged "queens" behind her continue to support her, but she's a heroine of naboo, so that's not an issue)
Queen of the year, that's awesome. Are they elected at Homecoming?