You can certainly paint the trim a different color in a bedroom. I wouldn't go around the house painting the trim in each room a different color, but you could create an interesting and charming room in the bedroom you propose.
First I suggest you select your furniture and bedding and draperies and then take the color from those for the room. It would be appropriate for the color to relate to other colors you've used in the house.

A combination I've used is walls of SW Chivalry Copper with the trim painted SW Weathered Shingle. It got rave reviews!

The, trim, wood tones can be complimentary, and different in color. They only have to compliment each other.

There is no one rule. Just make it artistic. The bookshelf can be an accent color near the large open concept for other rooms. room. Same for the furniture.

Many people do, change colors, purposly to break up monotony in the room and provide interest in color and wood color. Thanks!.

For example:

1. I have seen dark, or maple bottom cabinets combined with 'white' top cabinets (and with more contemporary style cabinets)

2. I have seen one cabinet wall as one color and rest a major color.

There are many ideas on here on Houzz.com that show the same thing, ideas as mentioned above.

I am a big fan of this house (can open pic to see the project) with different moldings in some rooms
http://houzz.com/photos/1500392

Thanks, this is very re-assuring. All these decisions are overwhelming!