I use heavier line, so I can release the as quickly as possible. The faster the release, the less stress the fish would be. I have also gone away from using lighter lines when saltwater fishing for the same reason.
If abrasion is a issue, then one possible remedy is to start using a fluorocarbon line. Either a few meters of fluorocarbon tippet (but then you have a knot to worry about) or track down same fluorocarbon mainline, its probably 4x the price of normal line but the added abrasion resistance could make it worthwhile. I see on trademe, that 250m of Stroft Flurocarbon is $89, although even stroft nylon is expensive.
Here is the Berkley Vanish Flourocarbon Mainline , it does not have a great reputation, but mainly because people use it for tippet material.
http://www.trademe.co.nz/sports/fishing … 040022.htm
or Krypton Flourocarbon, I know nothing about that brand, or is that a co-polymer… ummm
http://www.trademe.co.nz/sports/fishing … 284397.htm