SE5's map doesn't have enough precision to do very much with thick spiral arms, unfortunately. The map is only 67x49 squares. Plus, when I do place multiple stars into the spiral, it gets really ugly WP lines. Here is an example I had worked on last night:
Raapys:
It only takes as long as determining the a,b,c parameters for the polar logarithmic function. The real kicker is coming up with decent parameters that make layouts SE5 can work with.