I’m not necessarily disagreeing with your characterisation of different outcomes based on size / density and sophistication of pre-colonial populations, but you are factually wrong on commonwealth membership:
Africa
Botswana Cameroon Gambia, The Ghana Kenya Kingdom of eSwatini Lesotho Malawi Mauritius Mozambique Namibia Nigeria Rwanda Seychelles Sierra Leone South Africa Uganda United Republic of Tanzania Zambia
Asia
Bangladesh Brunei Darussalam India Malaysia Maldives Pakistan Singapore Sri Lanka
Caribbean and Americas
Antigua and Barbuda Bahamas, The Barbados Belize Canada Dominica Grenada Guyana Jamaica Saint Lucia St Kitts and Nevis St Vincent and The Grenadines Trinidad and Tobago
Europe
Cyprus Malta United Kingdom
Pacific
Australia Fiji Kiribati Nauru New Zealand Papua New Guinea Samoa Solomon Islands Tonga Tuvalu Vanuatu