I don't think Yzerman should give up on rebuilding. The arguments I hear for giving up are based on a 6-game win streak at the end of a 28th place season and/or hinge on Athanasiou becoming something akin to the next Brad Marchand. I sense a bit of wishful drinking going in that.
We're counting a lot of chickens before they've hatched. We don't know if we can count on Larsson yet. We don't know if our best defense prospects aren't guys who you'd rather have on a second pairing. Our best offensive player didn't rank in the league's top 40 for points, and some of the guys in supporting roles have nagging issues with things like competitiveness. Some of the forwards in Grand Rapids still have a ways to go if they're ever going to turn out. Plus we have some bad contracts that will be on the books for a while. We have players who don't cut it, who we wont be able to get rid of for years.
What I would like Yzerman to do is clean house, get rid of as many of the guys as possible who we've had from before the rebuild started. Also, the guys who aren't really a part of the rebuild, but who weren't around before the rebuild either, make some changes, upgrade them wherever possible. Yzerman should make the team his own as much as he can. And of course, get us some good draft picks. In short, what any GM should do here, especially if taking over a new team. I believe Steve will want to succeed or fail on his own terms, with his own team, not with Ken Holland's team, anyway.