Who do I keep of these 3

Ppr league (full point for a catch, 3 bonus points for 100 yards and/or 10 receptions). 14 teams. Each team can keep 3 players

I'm definitely keeping Adrian Peterson and Greg Olsen. Olsen because I feel the drop off from TE2 to the rest of the field is significant.

I need one
Ben Roethisberger . But I keep hearing he'll backslide on last year's stats. And no Bryant may hurt TD totals.
Jarvis Landry. I like him. I hate Tannehill. I like him to Derrick mason who was an undervalued stud in our league for years.
Or John Brown. Concussions scare me. But I also think he could go 70/1200/12 if Palmer stays healthy.

Btw, I'm a Steelers fan and I usually don't even draft Steelers, but Ben has had some HUGE games in the last 2 years. I'm leaning toward keeping a WR and trying to grab Derrick Carr or Jameios Winston or Marcus Marriota in the 3rd or 4th round (which are players 70+ of the board)

Any help. I always seem to make the wrong pick in these situations

Landry is a target magnet and hopefully the fins OF line stays healthier than last year which helps tannehill as does Adam Gase. 

i would get rid of brown just because of the concussion aspect.  Big Ben has his injury issues but he is a great fantasy QB when healthy.  Jarvis Landry is going to do well.  I like John Brown don't get me wrong but i don't like his situation.