From the recent safety training course provide by Jen Kleck:

Area (boat traffic, splinters on the dock, weather, etc)
Boat and equipment (floatation, no broken rudders/skegs, deck lines, spray skirts, PFDs properly adjusted, spare paddle, tow line, etc)
Communication (within group: signals, whistles, etc & outside: cell phone or VHF radio (SPOT device))
Doctor (medicines, first aid kit)
“Emergencies” or incidents (what to do if there’s a capsize)