When you consider that most people don't become life-long horse owners, this post tells me that are in it for more than show ribbons. Most people start looking around for something else to do with their horse. Trail-riding Western or showing Western is a good choice.
EVERY discipline teaches your horse balance and good manners. If you sell your horse in the future these things are the only guarantee of a possible good move for your horse.
I say, go Western for awhile. During the off-season--next winter--do some online research. I don't think many people are aware of how these styles and disciplines evolved, and how similar they really are.