Full DSP support when transcoding is still something I want, and it's on our list of good intentions. However, the list of good intentions is long.
There are two workarounds:
1) Disk writer (Options > Audio)
2) Sync to a virtual handheld with conversion enabled
I'm not sure about full DSP support for Media Network / DLNA. I like the idea, but some others here think it would add too much complexity to Media Network.
(p.s. great avatar!)