When it comes to my iPhone, it can't have enough RAM or flash storage IMO. More is always better. Which shouldn't surprise anyone when we're talking about a device that can be used to edit an HD video, among other things. It's a full computer shrunk down to the size of a pocket.
But the watch should never be used this way. Apps should be lean and fast, even after native app capability gets rolled out. There should not be a lot of graphics. So IMO 6 GB is actually a ton of storage for a watch and I'm not worried about this number.