Out of 4 different damsels that I previously had, yellow tail was the least problematic one. But was still problematic. I'd stay away from damsels. You may get lucky with a good one but odds are against you and if you have rocks in your tank good luck getting them out once you find out that he's problematic. Putting another clown in there may go either way as well. I guess It will most likely depend on the size of the new clown. You probably want to get one that's considerably smaller or bigger. Not the same size. I'm thinking the tang will be your best bet. However, If someone disagrees with me, I'd take their word over mine
I'm only about 6 months into the hobby. My hippo and clowns get along pretty good though.