The next two easy blocks in my quilt are Hourglass and Square in a Square. Both finish out to be 9 inches. They are good starter blocks for working with triangles. As the quilt progresses and the blocks get more complicated there will be many more triangles.
The Hourglass is also known as a Quarter Square Triangle Block or QST. It is easier to make 2 blocks than it is to make 1 so that's what I did. The picture is of 4 blocks, not one block made up of 4 units but it is fun to combine multiple hourglasses in one block.
For both colorways I used a directional print and it's easy to see where the quarter squares are in the block. Since you want the edges on the straight of grain making one would waste fabric and by making 2 blocks at once, you can deal with piecing squares together instead of triangles.
There are plenty of QST tutorials to be found. I started with 10 1/2 inch squares to yield the 9 inch blocks.
The square in a square can also be pieced using squares but I actually cut triangles for the corners in this block, Each corner is half a square and I had to be careful to get the stripes all going the same way (and with the hourglasses above). Again, there are many tutorials to be found for making this block.
The center square is 6 7/8 and the corner squares are made from are 5 3/8 squares cut diagonally.
Here's my modern version. I love the colors and circles.