Originally Posted by MsEithne

Why not treat each block as a min-quilt and do whatever suits that particular block?

Some might be echo quilting, to make an applique pop more or to emphasise piecing. Some might have motifs. Some might have filler designs like grids or stippling.

I think if you aim to give each block around the same amount of quilting, it will look uniform overall. But it would also have some of the fun of an "I Spy" quilt, as people looked to see how each block was quilted.