Spectra line imo doesn't matter. Mono I believe yes. Clear, gray, pink, blue??? I use Izor 1st string blue. Russ Izor made that color because it disappears in the water similar to flouro. At least that's what I've been told and its worked for me.
I've been using braid for years, and have tried straight braid with no luck. Only with a mono or fluro topshot. A friend of mine did catch a big trout on 6# straight braid many years ago when spiderwire first came out, but that's the only time I have ever seen it. I think mono and fluro colors vary with water types. Some guys swear by that red Cajun line when fishing for catfish. I don't know why.
Some clear mono will actually glow like a long thin flourescent bulb underwater,on a sunny bright day....i forget what its called,but i have actually seen this with my own eyes.Thats why a floro leader is always a good idea,that light gets terminated at the knot,on top of the fact that its floro.
Also,I have seen that multi colored line underwater actually dissapear...never the less i still dont use that line,just me I guess.
Last summer on a 3/4 day I used Big Game steel blue and did great. I was hooking fish left and right and no one around me was getting anything. I don't know if it was the line color but it was strange.