Streets meeting at less than 45 degrees
When streets meet at less than 45° the default turn instruction may not end up being true to life. The instruction may be "stay to the left/right" when drivers would consider it a turn, or "exit left/right" when the driver would consider it a "stay" or "turn". Allow the segments to meet at their actual angles and create an instruction override so that the instruction the driver is expecting will be given.
Also consider: The departure angle in Waze Map Editor is also shown in the app closure interface. Angles which are too close (under 20°) can overlap in the app, and so should be avoided.