The term itself leans heavily to the "They are an emotional, and imaginative person" side. However, modern use typically just implies that they have an amorous personality, since that is a more readily understood use of the term, as the implications are a little more specific.
ie
Saying someone is romantic (meaning emotional and imaginative) can imply that someone is a fanciful thinker, an eternal optimist, impractical...
Saying someone is romantic (meaning amorous or suave) just means that they can easily gain endearment from and instill pleasant emotions in the opposite sex.
Which way is simpler? That's how I look at it anyway.