I agree -- Driver support is the biggest thing lacking in the Catweasel MK3.
Another thing I'd like to have on a future version is better noise reduction on the SID sound output -- especially when the SID isn't in use. I get lots of background buzz on mine. Enough that I mute the input that I have the card leading to, when I'm not using it. I like the SID sound. I just don't want my computer to sound like a beat-up C64c (background buzz, pops, clicks) all the time! ;-)
A USB version would be cool, though, as well. :-)