I think its more important to learn techniques instead of blocks. Scant 1/4" seam, accurate cutting, half square triangles, quarter square triangles, matching seams, pressing & starching, flying geese, basic paper piecing. With learning the techniques, you can turn those skills into any block you want.
Craftsy also has free block of the month classes that you can sign up for if you want to learn a wide variety of piecing techniques.