Canada → New Zealand → Australia → Fiji → Vanuatu → Papua New Guinea → Micronesia → Indonesia → Malaysia → Philippines → Vietnam → Cambodia → Thailand → Laos → Sri Lanka → Maldives → India → Nepal → South Korea → Japan → China → Mongolia → (Trans Siberian Train) → Russia → Ukraine → Romania → Bulgaria → Greece → Macedonia → Serbia → Croatia → Hungary → Austria → Czech Republic → Poland → Lithuania → Latvia → Finland → Sweden → Norway → Denmark → The Netherlands → Belgium → UK → Ireland → Iceland → France → Germany → Italy → Spain → Portugal → Morocco → Algeria → Egypt → Jordan → Sudan → Niger → Mali → Senegal → Sierra Leone → Burkina Faso → Ghana → Togo → Benin → Cameroon → Gabon → Congo → Uganda → Kenya → Rwanda → Tanzania → Zambia → Malawi → Zimbabwe → Botswana → Nambia → South Africa → Argentina → Chile → Bolivia → Brazil → Peru → Ecuador → Colombia → Venezuela → Suriname → French Guiana → Trinidad and Tobogo → Grenada → St. Lucia → Martinique → Dominica → Antigua and Barbuda → Puerto Rico → Bahamas → Cuba → Jamaica → Cayman Islands → Panama → Costa Rica → Nicaragua → El Salvador → Honduras → Belize → Guatemala → Mexico
I think that you have to think once again about your route. Many parts of that route don't make any sense at all from a transport point of view. For example, it would make sense to visit Burkina Faso on your way from Niger to Mali. However, you plan to go there from Sierra Leone (BTW, How? Those countries don't share a border and there aren't direct flights between them) which will be (far) more expensive. Only an example, I could quote many more.
As I said in the above post, I have been researching this for a long time. I'll state it again. I have been researching the countries I want to visit for a long time. I know the requirements to enter each country.
...but it doesn't seem you researched how to go from one country to the next one or Am I wrong? For example, How do you plan to go from Sudan to Niger? And from Papua New Guinea to Micronesia? Only two examples, I could quote more.
In short, I think your first work should be to make a logic route (i.e.: without backtracking when there isn't any need to backtrack, avoiding difficult and expensive flight routes when there are easier alternatives changing the order of the countries you plan to visit...).