Hicks is joining a team well known to give opportunity and reward performance, with a healthy locker room chemistry and a winning culture. If his focus and work ethic aren't up to it he will quickly follow the Albert Haynesworth progression through the depth chart, but I don't think that's very likely. More likely is that he responds to the peer pressure and competitive expectations by applying himself and performing to the levels he has attained in the past. Worst case is, after doing that he gets a good deal somewhere else and the Pats get a compensatory draft pick for losing him to free agency. Best case is, he likes it here, we like having him here, and he gets a contract extension and sticks around for a few years. Good upside, not much downside, for a reasonable price.
Also see this as a good thing for Hooman, he gets a better chance to showcase his talents in a contract year. I sometimes wonder whether Belichick considers such factors when he makes moves like this. Hooman has been a good soldier, this move doesn't screw him over as much as getting cut would've, for sure.
