Are the qualities Confucius believed should be pursued (humanity, wisdom, courage) in any way akin to Plato's forms--the purest and highest state of things? Are these the most worthy and admirable qualities Confucius believed could be attained?

I think they share some similarities. Both Plato and Confucius were addressing problems in government, and both argued for virtue as the means to attain a just society. Plato went further than Confucius in the account of the world: Plato defended a dualist view that Confucius did not adopt.