The way I originally learned to do CS on squan was by connecting all 8 edges in a row, then using an alg (>scallop/scallop>barrel/barrel>kite/kite>square/square).
I used cube master's tutorial: this CS method is a little less efficient than the one you're using (because you only reduce to one star case and not a potential 5), but you might want to try it.
To get any faster, you need to have a good understanding of what certain slices do to the shape of the puzzle, so if you're struggling with making star, I would suggest working on that first before moving on to more efficient methods (like reducing to scallop/kite or scallop/scallop).