Just had a look at the DOI line-up and it's really strong, IMO. They've covered all the bases with that group and the only one I hadn't heard of was the guy from Eastenders who will presumably be quite famous to 8 or 9m people. They are going to need it though. The ratings have tailed off in the past couple of years - didn't it beat X Factor and Strictly in terms of series average way back when it began?
What will help DOI most is avoiding Call The Midwife.