That are 16 "colored states, so we can keep 7 more and have to get rid of the rest: (Assuming that UK and Dominions are considered to be one state)
Lets decide on keepers...
Asia (none) - Korea goes to Japan, Siam divided between UK and France, bnepal+Bhutan become British, Afghanistan becomes british and/or Russian, Persia divided between russia/UK and OE) Arabia divided between OE and UK.
Africa - (none) Liberia get US dependent, Ethiopia goes to Italy, Boer Republics to Pritain, Morocco spanish and French
Europe (2)
Switzerland
Greece
Luxemburg joins Germany
Balkan states get annexed (Montenegro and Serbia to A-H, Romaina to Russia and Bulgaria reintegrated to OE) - Microstates are swallowed bey neighbours)
Americas (5)
Mexico (Middleamerican states join more or less voluntary/prevent influence of US)
Brazil (Uruguay - once was part of it)
Argentine
Chile
Peru
Peru conquers Equador/Columbia
Venezuela divided by greater Peru/UK/Brazil
Bolivia divivded By Peru/Chile/Argentine/Brazil
Paraguay divided by Argentine/Brazil
Haiti/Dominica US territory
I believe that covers it.
How to come this? well no idea
23 is hard especially the Balkans and Sozuth american nation are hard to divvy up
If you said 30 (i.e. 7 more)
Siam
Persia
Serbia (+ Montenegro)
Romania
Bulgaria
Columbia
Venezuela
35 (5 more)
Bolivia
Paraguay
Uruguay
Liberia
Afghanistan
30 is doable
35 is realistic doable