SnowRegen: Kuko bow is a uniq bow. Look at the wiki (theres a button on the top of this site that links you there) and search for uniqs -> exceptional weapons -> bows (normals, not amazon bows).

jmarr: paladins are really good atm. Im pretty sure that you can farm hell rifts with just rare items. I mean, not just random rares. But with some preferable stats and the mentioned resists it will work, yes.
As for the future, paladins probably get some nerfs and you may be just in hell when the patch goes live :P
Id suggest to play a class you like primarily and just play. At least until the next patch with its balancing comes.