oh oh,,,I understood your question when I read again. I should read carefully. sorry about that.
you can still say "당신이 좋아요" right? I think you are stuck there.
It doesn't mean "I like you" at all. It means "you are good"
Yes, you got a good point of Korean.
because "you are good" is almost sounds like "I like you" in Korean.
좋아요 is like a short version of 좋아해요 in many situation.
and there is not even subject "I"
so, It should be "나는 당신이 좋아요" means "I like you"
so, in this case, There is no differences between 좋아해요 and 좋아요. only 3 letters and 4 letters. lol