Depends on your scoring system is, what you value more and who you can grab in the 2nd round...So coin toss between Charles and Brown imo...
If you think a WR1 will be available for you at the bottom of the second round go RB...
Personally I don't see that happening in my league (I pick 4th in in a 12 teamer) so I'm going Brown...
Standard league (no ppr). No bonuses for long TDs or anything. Only outlier from normal leagues is that passing TDs are 6 points instead of 4.
It's a 14 team league, so my best bet for a WR 1 in the back of the second would be a Randall Cobb-type, but even that will be pushing it since a few people have first/second round-grade keepers like ODB and Luck locked up at later-round values.