Arkenwheel works for a hippiemancer pretty well, too, as well as the great punnage with his title. So yeah, I'm thinking either 5 or 8 tools.I think however that the next tool will go to Parson, and with him being a hippiemancer I'm more inclined toward a signamancy tool.
EDIT However, the fifth tool would be aligned to all schools, rather than any specific school which would mean, by all rules of punnage:
Charlie: Arkendish
Stanley: Arkenhammer
Wanda: Arkenpliers
Rockwell: Arkensaw
Lord Hamster: Arkenwheel
That is all.