As an adjective, enhanced describes something that has been increased or made better, like a weather report whose enhanced maps show viewers exactly where a storm is taking place — the old maps couldn't do that.
The Old French word enhaucier means "make greater, make higher or louder; fatten, foster; raise in esteem," and is likely the origin of the verb enhance. So something that has received this treatment has definitely gotten an upgrade. In fact, upgraded is a good synonym for enhanced. So, if you find yourself flying in the first class, you would expect enhanced menu choices and a more comfortable chair.