Getting to an adjacent topic, but yes, there is little logic in thinking that, as long as the server device has sufficient processing power, that the packet stream across the network to the rendering device could be any different. That's the beauty of Roon's configuration.
I would also agree that DACs can sound different and that different inputs on a DAC may sound different (optical vs coax vs USB etc.) albeit I think a bigger influence is the analog implementation of a DAC. Thus, playing around with different configurations may result in something more pleasing.