Mine is exactly centered, and I love it.
I didn't specifically choose my map for it, it might actually surprise me if I did notice the secret beach at island map picking. I know the thing that really stood out to me on this map was the rivers and the way cliffs were structured that made me realize I could easily make a vast part of the island accessible with a few ramps and bridges.
My secret beach is behind a cliff, so I did some terraforming to get enough room for a ramp. I like having everything accessible without having to use vaulting poles or ladders

. The ramp lines up with the left side of my secret beach, because to get it in the middle I would also have had to destroy a bit of third level cliff and I didn't want to do that. But it leaves room for me to decorate the right side a bit, I put up a barrel, a bucket, and a 'wanted' sign

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