I still think a good in-house artistic coach would be great even if Igor's teams use outside choreographers because they'd have somebody there every day continuing to make tweaks, look at the movement, look at the program as a whole and work with Igor and get his input with the elements and technical requirements/skater's ability and stamina, to make it all work together.
I think a lot of the best coaches end up tweaking and changing outside choreography because once the season starts they are responsible for making sure it's a great competitive program that maximizes all the points while being "entertaining" and "engaging". For Igor, I think there needs to be someone on the level of Camerlengo at least to help with that like he had with Marina in the past. Even if some fans still don't like it, at least it would be more than just arm flailing and extraneous movement not meaning anything that Igor tends to be guilty of when he feels like he needs to fill space in-between elements with choreography.