Good start. Way better than any of my first sculpts. You may want to start using dynamic topology if you want to get more into your pieces while using the minimal amount of ram. While subdivision of an entire piece gives a nice uniform mesh, it also is just incredibly wasteful. 3 million vertices should be sufficient to add in a full head, neck, shoulders and quite a bit of hair if you need. You could probably do an entire body and still add hair with 3 million. I’ll use an example from my previous post.
If you scroll down to the greyish creature. It’s only 416k vertices. The dumb looking chihuahua/rat thing is at about 800k. But, that’s more due to the eyes which are probably an additional 400k by themselves. Not really trying to keep the numbers down, they just aren’t really needed when using dynamic topology compared to subdividing the entire mesh to add details. They could easily be lower, and no one would be able to see the difference. But, the opposite is also true, I could subdivide the entire thing and be in the millions and still no one would be able to tell the difference. They are just doodles, and could probably use some additional detail, but the overhead is there (if needed) using this method.