The Best Drawing Program is one that is no longer supported by it’s corporate owner. The Best Drawing Program is Freehand hands down.
The reason Freehand is the Best Drawing Program is that it is intuitive to use, fairly light weight in it’s memory requirements, and it has a powerful set of tools that are easy to use, and an interface that is minimal as compared to the most complex and obtuse program named Illustrator.
Adobe does it’s customers a disservice by refusing to update Freehand to keep it modern, lean and mean, and working on the latest operating systems for Macs and Windows. So without further delay save the best drawing program from total demise.