Here are a couple more Mii characters I came up with while listening to Randi Rhodes today (and screaming obscenities at morally bankrupt Republicans, but that's another story). I'm hopeful that Nintendo's actual Mii creator will be as impressive as this. If anything, I'd like even more control over how my characters will look.
Obviously, Nintendo wouldn't want things like uploading photos or jpegs to add to your Mii, since there's the risk of snarky kids posting something offensive.
One additional feature I would like - and this is really just dreaming, so don't take it as anything remotely newsworthy - would be the ability to record a short voice sample for your Mii character. I'd just like to have this guy with the big head shout out, "Froyn-layvin!!"
I suspect this little feature - almost a throwaway, really - will prove very popular with people. It's going to add to the Wii's immediate social appeal. Also, if you didn't know, Nintendo intends for your characters to mingle around, into others' waiting rooms on their consoles, and in the games themselves. The table tennis game on Wii Play is an excellent example of this. Ideally, user interfaces on the internet will evolve into something more iconic and intuitive, as we move away from keyboards, mice, and joypads, and into the immersive age of holodecks and "Minority Report."
It's kinda weird when you contemplate the Holographic Paradigm, which suggests that the entire world (and the whole universe) is really a giant hologram. Cue the Twilight Zone music!
If this feature really does become popular, expect Nintendo to introduce new features and more customization options over their Wii Connect feature.