Do we need 400 tan shapes?

When you cant select the shape you want 400 seems excessive. I get no sense of progression. I even saw the same shape come up twice, are there even 400? Or do I need to keep hitting the new button and hope I get lucky. Moving shapes around often obscured other shapes. Tapping to rotate feels tedious. The grid is not a bad idea, but you need to be way too precise when placing your tans. The tan shapes I saw so far seem way too easy. Nearly all of the are obvious from the beginning, not much challenge.

Cybexx about Tangrams