Official comment
For mapping activities that require high accuracy we always recommend doing some post processing of our raw geotiff to make things work for you if you have the skill set (rubber sheeting, thin plate spline, etc).
With any post processing you will be responsible for the final presentation of how the map is shown and what base maps are used since it will be outside of Maps Made Easy at that point.
We have had a few users map river and coastal sections longer than this with our Linear Flight planning with great success.