I've drafted first and last
I still think drafting first is an advantage, but I actually preferred drafting last.
There's more pressure on drafting first. I've drafted first twice. I was so paranoid not to screw up, that I ended up making safe rather than spectacular picks.
I've drafted last only once, but have drafted next to last a couple times and usually have been near the end of the line. I tended to have a more relaxed attitude about my first round pick and ignore early season stumbles. Last year I took Kansas with the last pick of the first round. They were predicted to be tough but had a lot of shaky games out of the gate. But they righted themselves and ended up being a good pick.
With the a-larges, I think the advantage even increases for drafting first. By drafting #1, you get to draft first in 5 of 9 standard league rounds. You'd draft last among the at-larges, but RBS proved last year that it shouldn't really matter (he hit a homer with Del St which was practically the last a-l taken).
Of course that's all on the theory that standard league teams are drafted rounds 1-9 by most people, and that the majority waits for the final round for at-larges.