Oh, yeah, there is also the option of agility to raise speed because a lot of things outspeed kingler, you do considerably less damage but if you go with swords dance kingler will take a beating. Up to you
kinda, once you have a few good pokemon (ev trained or otherwise) and access to the battle tower/battle frontier/battle subway you can buy them for 1 battle point (currency for said facilities)
with a exp share the pokemon holding it gets the evs as well as experience even though it doesn't battle (I'll go into technicalities later), also a pokémon cant gain experience and levels without gaining evs outside of using a rare candy which lowers stats so you shouldnt use it.
btw, if you are not following me just say and I will try to make it a little easier to comprehend