I understand the Gronk picks because our defense hasn't been as good as it was in the Superbowl years.
That said, it's clearly VW with no close second. I can absolutely imagine how our defense would look without his presence and it's shocking. Tom can still put up good points without Gronk. I doubt our defense could stop drives without VW.
Also, with all the new receivers, I'm not sure we're as reliant on Gronk this season as we were the previous couple of them. Not to say he's still not the 2nd best on offense, just saying we might be able to replace a larger portion of that production than we could a year or two ago. (Especially with the monster run game we might just have.)