I m going to add
PRI (Praslin, Seychelles) - small, but they do have 10 props a day
FGI (Apia, Samoa) - the city airport, with only props to American Samoa
SCY (San Cristobal, Galapagos) - only one scheduled flight per day (two in season)
TCB (Treasure Cay, Bahamas) - only a couple props a day

Other small airports:
MHH - Marsh Harbour, Bahamas
HEH - Heho, Myanmar
MAJ/KWA/TKK/KSA/PNI - Island hopper
PPG - Pago Pago, American Samoa
YHM - Hamilton, Canada
MMY - Myiakojima, Japan
TAB - Tobago
MYY - Miri, Malaysia
UGC - Urgench, Uzbekistan

smallest of them all - Thorshavn Heliport, Faroe Islands. The hut is the checkin, the toilet, the waiting room, and flight control all into one.