Thoughts on my speaker selection?

I am no expert but I love my JBL studio 590’s.  And I have a PS Audio s300 amp.  They sound great. A true story.  I was in the Harman store in NYC and they were demoing some nice popular well reviewed Revel book shelves that cost 4 times the price. We listened to Dark Side of the moon on some high end gear.  I told him my JBLs sound better. He said it was because my JBLs are full range flour standers. True story.  My only advice is obvious. Make sure you can return them after you listen to them.  Good luck. And have fun. 

Based on your price point you may also look at used speakers.  

This are all used prices for the most part. The only one that may be a new price is the first price listed.
I'm also hard considering the HSU CCB-8 center speaker and maybe 3 for LCR.
Anyone use those?

What is your total budget?
What surround system (5.1,7.2 etc)? 

budget isnt really set. it varies from $1k-2k, with a preference of $1k obviously.

Trying to avoid the point of diminishing returns essentially.

I don't need any recommendations for non LCR speakers, but I have running 5.1.2.