For years we have been unsatisfied with the quality of boundary files for Canada publicly available including from government sources. Many products have trouble in coastal areas and miss many coastal islands, peninsulas etc. Many global boundary files are too coarse and miss borders etc. I have been considering using the land cover classification of Canada (2015) raster to try to create one but aggregation of coastal waters and lakes in its formation process makes that challenging.
Any advice/are there any really high quality datasets out there that accurately represent boundaries?