Dolphins beat writer Chris Perkins believes that WR Jarvis Landry is the player most likely to have a breakthrough season in 2015:
A breakthrough season would be improving on the 84 receptions for 758 yards and 5 TDs he had last year as a rookie. There’s a good chance that happens now that TE Charles Clay and WRs Mike Wallace, Brian Hartline and Brandon Gibson are gone. Tannehill is familiar with Landry, and Landry showed he’s got good NFL skills. He’s got good hands and can get YAC (Yards After Catch).
Landry was the #42 WR in standard formats and #30 in PPR, so as a high-volume slot receiver, he's going to have more value in PPR formats. The Dolphins lost four of their top six most-targeted players: Mike Wallace, Charles Clay, Brian Hartline and Brandon Gibson. They have been replaced by Kenny Stills and Jordan Cameron, but Landry's role should expand as well. He only played 62 percent of the snaps on the season, and didn't start playing consistent starter's snaps until Week 9. Over the final nine weeks, Landry was the #15 WR in PPR formats (and #23 in standard). He is currently the 24th WR off the board in early PPR drafts.