I understand that in-application editing of title blocks will soon be available. I hope this is soon as I see that many of us need this feature.
As an idea until something better comes along or even as a more complete solution, it would be great if someone would create a script that could import and export between SVG files and Fusion 360 templates and title blocks. SVG templates for FreeCAD can be created using Inkscape and even though it is a bit cumbersome, it works great in their latest release. SVG parameters can be created and edited easily in Inkscape. This would give those of us that do not have access to Autocad a way to create good looking drawings with appropriate title blocks or imaginative template styles.