"We all love blue."
I think this should be “我們都喜歡藍色的。” but I'm not a native speaker, so i can't say that with confidence.
Your 的 here is not needed if you just want to say you like the colour blue...
If someone asked "what colour shoes do you like?" you could say 我喜欢蓝色的 meaning I like blue (shoes) because the blue has now become an adjective describing the shoes. (You dont have to mention the shoes again as they can be assumed from the question).
What's the purpose of 的 at the end of your sentence? Is it a pause, before you go on to reveal an object that is in blue?
的 is often used at the end of a sentence to express certainty in something. For example, you might ask:
那，你会做吗？(Can you do it?) 会的. (I can [I'm certain that I can])
So when one says 我们都喜欢蓝色的. It means "We like blue." (they're certain that they all do / the person speaking is certain enough to speak for everyone)