I'm currently working on a Cody Country pattern, the U. S. Army Seal for my DH. It uses on full cross stitches with 35 different DMC flosses.
There are a lot of single stitches scattered around the pattern. I started stitching this two years before I found out about doing what is called a pinhead stitch. Since I had already started stitching, and didn't want to undo what I had done, I keep doing them the same way as before. You can see it done on a You Tube video.
It probably would have been a good idea to have gridded my fabric before I started stitching too. Occasionally, I get off kilter a stitch and need to redo it. It's also shown on a You Tube video.
The directions will include a list of DMC floss needed, a color guide, how many strands of floss to be used, but not how many skeins each color are necessary. On the ECS web site it shows only 1 skein of 310 Black is needed. I've already used 2+ skeins and I'm nearly half finished. You may need more than you think.
You can use DMC 310 Black to backstitch the details you think would make it "pop". I do this frequently. It's more work, but it like the look of it on my cross stitch projects.
I hope this information is helpful to you. I'm just a stitcher who saw your post, not an employee of ECS.
Diana