It's easy to validly prove anything with logic if your premises don't need to be sound.

If your premises aren't sound then how can you prove it with logic?

Buddhism is filled with premises that must be taken on faith, as they are not provable statements.

What are those premises exactly? I'm sorry being general isn't the way I like to have these types of discussions.

Saying that karma and rebirth are metaphors sounds exactly like a Christian saying something from the bible is a metaphor.

That's true, metaphors are used to teach because they work, philosophy uses metaphor, religion uses metaphor, nearly every good teacher uses metaphor. No one except religious groups want you to believe the metaphor literally, they only want you to understand the point the metaphor is trying to illustrate. Christians and other religions want you to believe the metaphor literally because that's just what they do, they worship these metaphors and take them literally. Buddhists like most teachers solely use these metaphors to teach, you don't need to believe the metaphor literally to be a Buddhist nor do they even really want you to focus on that because then you would be missing the point of the metaphor.

I don't see how worship is a necessary component of religion

Then what do you consider makes a belief a religion? A belief of something that is supernatural? Then if someone believes in ghosts, aliens or vampire demons, it automatically becomes a religion? Again most Buddhists don't literally believe these things.

For the record:

religion: the belief in and worship of a superhuman controlling power, especially a personal God or gods.

Worship plays a huge role depending on where you go.

Okay, what do Buddhists worship?