Don't know about down your way, but up here :
I started Crappie fishing back in the 1950's and when mono became available we used 8# test. And it probably had the diameter of today's 10-12# test
I don't do much "tightlining" live bait, but I used 4# test Stren & Trilene lines for decades, and now use 6# test Vicious Panfish copoly line (casting/jigging), but I also use weedless jigheads.
If you're using litewire hooks, you should be able to straighten them out with quality line of 6# or 8# test line.
Now, I'm not much of a believer in Crappie being "line shy" ... and I've used hi-vis lines for most of the past 30+ years, and still catch my fair share of fish. Might make a difference in extremely clear water, but even on lakes with slightly stained water (with visibility of 3-4ft deep) I've had no problem catching fish.