Not necessarily a shutdown line, but we do need a bottom six that has a more defined, clear role, and can be trusted in all scenarios, and contribute offensively. Everybody lauded our depth last season, but Boston's bottom six rolled over ours (granted, Kadri's suspension hurt that a lot). This year, things are looking good...it seems as though Goat & Shore can be trusted to take all d-zone draws, and the 3rd line has more of an identity as a speedy, counter-attacking, transitional line than last year's 3rd line did.
But Babcock has always been a strength vs strength coach. Obviously you want all your lines to be able to survive a few shifts against any line without conceding a goal, especially on the road in the playoffs, but it's always gonna be Tavares up against other team's top centres, and Matthews against the second centres probably.
Last year JT, Marner, & Hyman were essentially a shutdown, or rather, matchup line. Started in the d-zone a lot, ended up in the o-zone scoring goals. Hyman returning will be huge, and hopefully along with that Marner & JT will return to form, because that line is vital to matching other team's top lines.