Mattel’s former COO, Bryan Stockton stepped up to CEO on January 1st, taking over from Bob Eckert. He takes the reins of a firm in rude health, with Barbie’s transformation continuing, new IP launching and a raft of Hit brands to bolster the portfolio further. But, as he insists to Samantha Loveday, Mattel’s challenges are no different from other any consumer products company…