I'm trying to see an upside to this, but... even ignoring the effective year off (thank you Charlotte Moore... but as she's effectively doing four jobs now she can be forgiven for losing track of the details):
Chris Chibnall is a fan and a nice guy, but that doesn't make him a good writer, at least for Doctor Who. His episodes have been at best enjoyably average.
I'll give him a pass on Torchwood season one, because it's clear that as staff writer on a new series which was trying to work out what worked, he was writing the test-out episodes that the freelances didn't want to do. And season two was better, so the personnel change-out was a bit unfair (even though Children of Earth is superb).
But... when Broadchurch was starting, he said in an interview on Radio Four that it came out of him being very disillusioned by a show-runner stint in the States (Camelot, I presume), so he just sat down to write something he'd like to see, regardless of whether it would sell. And that worked.
I think that's what he ought to be doing: one-offs (no second series), not trying to be a mainstream showrunner on a popular series. And particularly not on an SF series, let alone he one he loved as a kid.