The use of the opposable thumb is another significant factor which had already been achieved by apes enabling them to grasp things. Standing enhanced this quality as they were now able to run with their hands free to use weapons. Standing tall, in a group also makes you look stronger to predators, and rivals such as baboons. The other advantage is that you expose a smaller percentage of your body (top of head and shoulders only) to the sun, and whilst most animals are seeking shade in the hottest part of the day, humans were able to keep going for longer.
Tool making can be seen in chimps and benobos. But this again was a vital ingredient in evolution.
More brain power is an expensive commodity in evolution, but bipedalism seem to have given early man the best possible reason for this attribute to be useful.
Once growing brain power became useful with upright, tool carrying humans, this aspect of evolution has enabled the ballooning of the brain. This seemed to have stopped about 6 thousand years ago, with the invention of sedentism and agriculture. Evolution now seems to occur in the abstract realm of knowledge. Sadly many have not kept up and still want to repeat the "knowledge" of our primitive ancestors and continue to believe in Creation
Evolution has always been an exciting science fiction story.