Ranger Mainhand
 

Revultant Whip or Lamentation?

Entirely depends on level. At higher levels the mainhand damage bonus which is level based becomes very significant so the faster weapon applies this base damage over and over again. I'm not sure at what level you may consider switching to the whip but I believe it will beat out a lammy at 55+.

Based on the back of the envelope numbers I ran Lammy wins out even at 60.

How does a Nightwalker compare in mainhand?

Toooooooo slowwww?

Lammy or lupine is probably where you want to be

lammy and whip are both inferior to jade mace or lupine dagger (obviously lupine > mace because of stats and proc)

also all of the above are inferior to fayguard parrying dagger by a lot

by my calculations of course.

Meh, I'd take a loss with the extra 1dly on Lammy in exchange for the stats.
And snare whip is fine for offhand IMO.

damage wise, whip is a terrible offhand... the only reason whip would be any good is at max level with main hand damage bonus and the 14 delay and still it is less dps than a lupine dagger or jade mace.