Is a logical question still where was this aggressiveness last offseason when they had oodles of cap space and a bad roster? Either Wolf and Mayo were under some budget restrictions (paying off Belichick?) or Wolf was basically Chaim Bloom and could never pull the trigger on any significant move.
So I have a few thoughts. I'm going to ignore the attractiveness of the team (coaching, QB, etc). They are clearly more attractive with Vrabel and Maye, but considering the money they've thrown around today, I think difference is driven more by teambuilding tactics, where there are a few considerations.
The first is that I'm not sure what the power dynamic was between Mayo and Wolf last year compared to Vrabel and Wolf this year, so he may have a different level of decision-making power. Perhaps Wolf had more power last year, but less this year, in which case the difference is due to Vrabel's aggressiveness compared to Mayo's.
Maybe Wolf has the same power as last year. In that case, we know Wolf was brought up in the Green Bay system, where they largely stay out of free agency and focus on drafting and developing. He knows free agents are bad value, so he'd generally prefer to limit spending there. They took some low cost risks last year, which had minimal impact, but that experience could have shifted his mindset to take more risks.
There's another reason he'd be willing to take more risks this year. I would not be the least bit surprised if Vrabel pushes Wolf out in a year. He brought in Cowden, who he wanted as GM in Tennessee, so Wolf's replacement is already in the organization. Wolf won't be here next year if they fail in free agency and the draft again, so that adds some additional desperation with the moves he makes.