I'm almost ashamed to admit that Harvest Moon is one of the few Console games I enjoy playing (on an emulator)

I'd like to own a Wii, but I'm not in any rush, so I'll leave it till the prices drop a bit. It won't take long, it never does

But I'd say that challenge and fun whilst playing the game can easily make up for limitations in the Graphics,
The Wii will not support DVD playback, it's not pretending to be anything other than a games console, and I expect that the hardware in there, whilst not as advanced, will not be nearly as demanding of power or productive of heat.
It's a little more expensive than I would have liked, but like I said, that'll drop soon enough
