Here is Helen's second pattern, except that the colour scheme is different.
This reminds me of a pattern I struggled to create seven months ago. It now seems easy. Some of the concentric circles are narrower, and I made these transparent so I could use a gradient behind the pattern.
Black is more dramatic.
I decided to fill the shapes of the third pattern with bitmap images. In one of Robert Joyner's Skillshare classes I intentionally painted a page of 'mud'. When I attempted to scan it, I found it impossible to reproduce. I ended up taking a photograph, which gave more accurate colours. You can see my project at https://www.skillshare.com/classes/crafts/Essential-Skills-Part-Two/1009532158/projects/68201?via=class-details-projects-page
I saved fourteen scans, each different and none as muddy as the paint. I chose sections from one of these scans to use for this pattern, using squares instead of circles.
The above pattern is fairly flat because the values are all close, with the orange squares just a bit lighter. I chose sections from two other scans for the pattern below. Here the bottom and right sides of the square are darker than the top and left sides, which results in a quilted illusion. To match this I used a shadow around the circles.
Although I have created more complex patterns in other Skillshare classes, I found it enjoyable and revealing to explore what can be done with just a few simple shapes.