Thanks for all your help. I don't feel quite as overwhelmed as when I started
I think I'll go with the 468's for now. I plan to get two sets of eneloop batteries for each flash, and I think that should be more than enough as most of the events I will need these for have a large portion of the photography being done outdoors in good light.
And all that for close to $200 is very preferable to me right now. Once I have these in my arsenal I can take time to snag a good ebay deal on some 580EXII's when searching for a good deal isn't time sensitive.
I would appreciate a recommendation for an off-brand alternative to Canon's E-TTL cord though. I can foresee a few scenarios in which I'd want to move the flash off to the side, but probably not more than arm's length since my photographic style is rather active and journalistic/candid. Canon's cord is crazy expensive, but there are so many super cheap alternatives I'm not sure which one will actually perform.