Most profitable:

+12p -5h Referred to hint to spell 4 words in Morphos.
+3p -1h Referred to ancient tech terms in Civilization.
+2p -1h Illustrated 3 of 9 plots.

Least profitable:

+0p -3h Paper prototyped geomagic squares Friday night.
+0p -2h Unit tested controllers instead of models.
+1p -2h Wired about 30 UI and 30 components in Unity editor.

Key to estimates per feature:

p: players engaged.
h: hours worked.

I suspect a few more would play with all 9 plots illustrated, so now I illustrated all 9. You can play WebGL and Android here: City of Words