Depth of face- lot depends on the type of wood, time of year, rot, etc.
Where a 70% face depth is something to reconsider is the surprise gust of wind that slams that top hard. The wrong way.
Hinge thickness and integrity (clean grain) and wedging early speak volumes about control.
I will say one thing that alot will disagree with. Back boring from the hinge to the release strap maybe appealing to some and in some situations (heavy head lean and bad heart) may be considered. However, consider the back bore on centered stem. Face cut is good. No dutchman, hiinge is right thickness. Backbore goes well, leaving the release strap at the back.
But, the hinge has squirely grain or otherwise weak. Gust of wind slams hard from face to back; hinge cracks, and stem goes over backwards. Oops.
Wedges.