Looks like they found the perfect replacement for Vereen, this kid makes the catches, is very elusive after the catch gaining more yards and he can run. And James White is still on cheap rookie contract for a few years.
#3rd down back - Checked
As for the money, seems ok to me, he was out of the league a couple months ago and it's not like Belichick found gold, he is, as usual, taking the most out of a player knowing his strengths and weakness, if Dion is smart he knows he would have a hard time finding a job around the league if not for this opportunity and even after a good season, he is working in this system. It's not certain it would work in different teams and he most likely would be another RB rotating around the league for a back end of a roster.