There's a risk, returning kicks. The reason they instituted new rules on kick offs is because of them. Risking an every down player on special teams is a high risk factor, especially when it comes to the skill categories. That's why you usually find that the KR guys are marginal WRs, DBs, or in some cases, even RBs. They have the speed, but aren't really good enough every down.
There was a time when guys worked their rears off to make these teams, knowing it was their ticket into the NFL. In many cases, the only ticket. They write stories, and make movies, about guys like that. Vince Papale, of the Eagles, is a prime example. A special teams player, listed as a WR, who had 1 catch in 3 years in the NFL, was credited for 4 years I believe, but was yet, an important part of their team. He worked to become a ST dynamo.
Personally, I don't mind seeing Amari Rodgers returning kicks, but I'm not too fond of Doubs doing it. He figures as an important figure down the road for the Packers. He's going to defnitely be a good receiver, in my opinion.