Hiya~
I think your "Screenshot Showcase" (incorporated into RH DCC) is a bad idea. =/
If there is going to be a screenshot showcase, it should stand as its own thread. If people are looking through the DCC and making conversation, they most likely wouldn't want random images in the middle of everything, breaking up the on-going conversation. The same applies to people that are there specifically for the screenshots: I'm sure that they wouldn't want a bunch as random conversations popping up in the middle of all the screenies.
As a concept, I think a thread for RH screenshots could be pretty neat to visit every once in a while, but should stand as its own thread.