Hi,
I think what you are trying to do is not likely. First off, you posted in the 323 forum, this unit is no longer readily available in the US anyway, and has been replaced by the 320 - 325 series units. Power consumption for the 320 is roughly 16 watts to 8 at sleep, for the 325 it is 22watts / 10 watts at sleep. A major issue would be playback on your TV, there is a UPNP server on the NAS but unless your TV is capable of actually playing all of your raw video files itself, you would need some kind of media player. DLNA does not guarantee it will play every media codec and from the posts I have seen the support for various file formats is very limited for many TV's. Next issue is playback of multiple HD streams. If your source material is say 1080P x2 quality, I am not sure the 320 would be able to handle this with totally smooth playback. The 325 would probably be able to handle this, but the prices in Europe are likely going to exceed your budget and that is without any HD's. I think your current setup is actually pretty efficient, but at the very least, do your homework before going in the direction you are considering. Just my 2 cents. Good luck