Re: I want to add Steve Slaton, but...
I'm not sure I'd drop any of them for Slaton (actually, I'm pretty sure I wouldn't), but if I did, it would be White.
Last year, Taylor and White had the same # of TD's, and while LenDale had about 265 more rushing yards than Taylor did, when you throw in receiving yardage, there was less than a 100 yard difference. I don't know how your scoring works, so maybe that makes a difference, maybe it doesn't.
The reason I'd go with Taylor over White is because of Chris Johnson. Taylor's situation shouldn't change much. Peterson only missed 2 games last year, and even if he starts all 16 games this year, I don't see Taylor's role changing much at all. White on the other hand may still be the goal line back, but I just don't see his fantasy stats getting any better with a significant contribution from Johnson looming.
Being a D-bag and being factually correct are not in any way mutually exclusive!