That's great=好棒 That's good=不错 That's nice=有点意思 That's brilliant=太聪明了 That's awesome=酷 Sometimes, it helps to find the counterparts in Chinese. Try and think when is the last time you heard awesome and great were used, how they are different. I'm sure you will have some insights as well :-)

This is a very difficult question to answer because these words, while different in meaning, have come to be almost synonymous in usage. I would suggest asking the question again using only two or three of the words.

those words are an adjectives, and the adjectives can't be suitable for all things, so the first is more generic (good) so it can be synonym for all those words but less strong than great and awesome, as for brilliant is more suitable for the actions and achievements great fit the lasting things and actions rather than temporary ones awesome suits the appearances what is looking admirable, or even the hard thing like challenges or task. so you don't say wow a great flowers , but wow an awesome flower; it depends on the adjective object what is it.