All's fair in love and recruiting?

Much has been made of quarterback Riley Nelson’s impending transfer from Utah State to BYU. As in the past, when a player decides to switch schools — especially while that player is on a mission — it opens up a Pandora’s Box of speculation, debate and emotion.
Over the years, the BYU football program has both lost to other schools and gained returned missionaries from other schools.
NCAA rules allow schools to recruit players who have previously signed a national letter-of-intent and have gone on a mission ‘ after they’ve reached the 18-month mark of their missionary service.
Wide receiver Austin Collie received all sorts of letters from schools while he was serving his mission. Oregon, Stanford, UCLA and Oklahoma State all offered him scholarships during his mission, but, of course, he opted to return to Provo.
The Cougars currently have a few players on their roster who chose to transfer from major schools to BYU while, or soon after, serving missions ‘ quarterback Max Hall (Arizona State), cornerback Brandon Bradley (Louisville) and center Tom Sorensen (Vanderbilt).
Others, like quarterback Ben Olson, redshirted for one season at BYU, then transferred to UCLA after his mission. Defensive lineman Victor Filipe signed with the Cougars, then transferred to Oregon after his mission.
Should anything be done to regulate these recruiting scenarios with missionaries? Should the NCAA ban contact between coaches and missionaries? Should there be a stiffer penalty for players who decide to transfer while on a mission, such as being forced to sit out that first year?