Brazil is mired in government corruption and scandal and has failed to become even a regional power.

Russia is a pariah with a shrinking population and no real economy outside of petrochemicals

India is a more hopeful version if Brazil but still enormously corrupt. It’s also in conflict with Pakistan and China.

China is more likely to be the next Japan than the next USA. Huge debt from infra spending + population that will halve by 2050 is not a great foundation. They sabre rattle but have never in their history had a blue water navy - the minimum to be a credible military power.

My money is on places like Nigeria, Colombia, Namibia, Botswana. Places with relatively good governance and a functioning economic foundation, that are free of distractions from serious regional conflict.