On 2 strokes there seems to be an issue of them spooling back up to power slower than 4 strokes from a hovering attitude. Which props tend to spool up faster: low pitch or high, wide blade or narrow, lighter or heavier?

Low, narrow, lighter. Low pitch, WIDE blade, lightweight props usually yield satisfactory results.

Narrow blade scimitar wood or carbon fiber propellers.
Mejzlik or Menz

Get wood over CF

The lighter the prop the better, the lower the pitch the faster the spool but not necessarily the better performance [assuming your comparing it to another of the same diameter from the same manufacture]. Narrow blades in my experience do tend to spool faster and also have higher static RPM then there counter part, and strangely sometimes actually have more static thrust, although I have no explanation for this.