I would have taken Nelson, yes. But as PenguinHunter already said, it depends on your strategy. I always go WR heavy early in drafts in leagues where you need to start either 3WRs + a RB/WR/TE flex, or 2WRS + the flex noted.
In this particular mock I'm more flexible because it's only ten teams and therefore less player demand which in turn provides some flexibility in regard to strategy.
But let's say you're in a 14 team league, still standard scoring but you need to activate 3 WRs each week plus the RB/WR/TE flex option. That means each team HAS to roster at least 3 starting WRs x 14 teams = 42 WRs off the board at a minimum.
Now using 2015 fantasy production numbers look at the variance among the top 42 from last season HERE you see that to no surprise Antonio Brown is first at 246.2 total points accrued or 15.4 FPts/game. At the 42 position is Tyler Locket who finished with 104.4 total or 7.0 FPts/game. That's a difference in production of 141.8 total points or 8.4 FPts/game.
And you can see that once you get beyond Jarvis Landry (157 total or 9.8 per game) at the 17/18 position per game production drops to single digits. At that point the variance in production only amounts to only a 52.6 point swing overall or a 2.8 difference per game production level.
That's why I am gunning for those top 15-18 receivers in the earlier rounds. Because between 18-42 there's really not a significant difference in production. Obviously, there a players who unexpectedly under/over perform. You can't possibly account for every unknown. But you get my point.
Do the same for RBs. Generally a must start 2 RB x 14 teams = 28 must owns at the RB position. Using 2015 RB stats (also standard scoring). There were 13 players at double digit production per game, and that doesn't include studs like Foster, Jammy Charlres, Le'Veon Bell Dion Lewis, Todd Gurley, Thomas Rawls and Mark ingram and Lynch who played under 15 games due to injury. Include them when healthy and we're at 20.
You can do the same for QB too. But that's why I go WR heavy early and often.
EDIT: I should add that in PPR formats the variance noted above is even more evident. In ppr leagues I gobble up any player capable of catching a pass. Targets are a more reliable and predictive metric than TDs. The PPR helps offset any lack of TD production which is a more random and unreliable predictor of future fantasy production.