That’s a nice start you have there!
Freestyling is really enjoyable but even more so when you have a good base of anatomical knowledge.
I get the need to sculpt without references though, trust me, and it’s important to do so.
Only sculpting from reference or following tutorials can get old very fast!
A good exercise that will help you build up your anatomy skills, is to sculpt freestyle to your heart’s content and then revisit with a reference and start moving stuff around.
It’s a good exercise because it will highlight your misconceptions about forms (which we all have) and in that way you can remember it for the next sculpt much easier than say reading an anatomy book or just copying a reference image from the get-go!