It's probably a slight overpayment for Simmonds, who very well may regress a bit from the near-30 goal, 21 assist performance he put up a year ago. Then again, Simmonds did see more power play time last season than he ever had in his career to date. That led to 11 power play goals in total, and it's possible (perhaps likely) that his opportunities will increase both on the power play and at even strength next season.
His overall shooting percentage may regress as well, but not too drastically. Simmonds put pucks in the net on 14.2 percent of his shots last year. In the two seasons prior, he averaged a 12.3 percent shooting percentage.
As Hughes points out, though, Simmonds is only 24 years old, and the deal will lock him up through his prime. There's also the possibility that, through the ongoing labor negotiations, Simmonds' $4 million a year price tag gets reduced.