I mean, Democratic Socialism with very strong anti corruption measures is sort of like advanced anarchy - tribal, but on a bigger scale. It's a pretty good solution even without modifications.

I know communism is what would be ideal, but like you said, humans overall would need to become something they're not fit for it too work on a larger scale.

Other than that, finding a way to either fully restrain the corruptive influence capitalism has while taking advantage of it's positives or coming up with a system better than capitalism would improve things too. Personally the "inflationary credits" system is one I think could work if properly implemented.