hello.
rangers knuckleblades are excellent for bossfights (in dPs)
to be an awesome ranger id go all out str build, simply because str will add to the damage and you dont use any damage skills whith knucks on ranger.
also buy super haste elixers for long bossfights, ( if you get super haste elxers and your going to use them i suggest swapping your gloves for corbins bracers)
defensive spikes is alright skill when your using knucks...
also id have a bow so when you equip the bow you cast steady aim then unequip the bow and equip the knucks and you will still be on steady aim. so yes better attack and damage for 1 min ( i think 1 minute lolz)
if your thinking of using light heal id go 100 dex and rest str leave the dex alone forever

and buy diamond gear because it increases dex/str and vit.
also your hp wont need to be much because of the 100 dex and light heal. (just group whith a tanker and a druide).
this is just my 2 cents, and really does work for me. anyways id get more opinions if your serious about h2h build.