Leeching gives people with not much left to do...something to do and another job to grind out some gear on. I don't have a problem with leeching in itself really, I hate how the leeching system ruins the XP party system outside of Abyssea but thats something else.

String has a minor advantage in range for horde but you lose some accuracy, I only ever used it for the PUK ENM thingy cause I kept missing some of the puks using wind. Really there is no serious reason to bother with string and for gear I would go all out on magic acc/wind skill/singing skill cause all they are truely good for anymore is landing the correct threnody.