"Wow, nice content", "Cool post", "Great news", "Good job" - all these are basically spam comments. Most of the time they are posted via bots, without any concern about the actual post.
There is a new task created on the Condenser GitHub repo, which looks like that:
This patch will prevent short, meaningless comments to appear on Steemit and it will suggest to the user to upsteem the post instead.
From what I see, the task is still being worked on, so any new input should be still useful. A useful comment came from 
My suggestions - based on the comments that I usually get:
"nice","cool","great","sir","please","good","wow","super","extra","outstanding","go","up","upvoted","resteemed","follow","follow me","followed"
If you have any inputs to that issue, you can write them in the comments (please refrain from "Wow, nice content", "Cool post", "Great news", "Good job", I know you are funny, but still). I will try to compile a list of the most useful and post them to the GitHub issue, in the comments. Alternatively, you can go ahead and post on the issue yourself.
I'm a serial entrepreneur, blogger and ultrarunner. You can find me mainly on my blog at Dragos Roua where I write about productivity, business, relationships and running. Here on Steemit you may stay updated by following me 
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