Other then Clear lol It is all going to depend on water conditions. Different colored line works in different colored water. I would like to see a 2lb pink line. I thought Ande made some but havent seen it in years.
red/pink is the first color to disappear under water. so thats y its prolly pretty. But i use clear and clearish blue line, and i have never really had a problem getting bit.
I carry extra spools of Maxima Ultragreen along with spools of Maxima Perfexion and P-Line Fluroclear so I am ready for any water color I find. By the way just because Red in the first color to dissapear under water does not mean the line becomes invisible, it just means it stops being Red.
On my big reels I use maxima and its usually a greenish color and it gets bit. For local rods I use clear or pink ande. And for freshwater line I use clear.