I'd say it's still too early to say. The verdict on his run won't be clear until he finally gets around to explaining what happened with Cyclops, the mutant/Inhuman war, and the complete regression of the X-men's cause after the events of Uncanny X-men 600. If Lemire can make that story work in a believable way, then I think that makes his run work. If he botches it in a way that feels contrived, forced, and completely irrational, then he'll start inching towards Chuck Austin territory because this era of X-men comics is so muddled by the Inhumans push that it's already a major low point. And Lemire's failure to make the events of the 8-month gap feel palatable would only dig a deeper hole for the books to get out of. If that happens, another relaunch might be necessary. And it might take someone on the level of a Jason Aaron, Kieron Gillen, or Charles Soule to fix it. But I don't see Marvel putting those kinds of resources into X-men, regardless of how Lemire's run pans out.