Yes, I think a rectangular tub would look silly unless you changed the windows. Have you considered a freestanding tub placed at an angle? It wouldn't gain you any space, but would look less boxy. Like this:

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I've looked into it but I'm not crazy about those type of tubs. Are there any corner tubs out there that you would recommend that aren't so outdated? Or anything else you might recommend?

I would replace the tile on the step with something lighter ,fresher and more modern. I and a corner tub and really liked it!

I think if I were you, I would keep the corner tub. What is it you don't like? What are you trying to achieve in your reno? And if you post a floor plan along with your goals, you'll receive some ideas.