As far as the "Titan" part of the name goes, consider...
[card]Gorilla Titan[/card] (it
can be bigger than 4/4)
[card]Kavu Titan[/card]
[card]Marble Titan[/card]
[card]Opal Titan[/card]
I think there's plenty of precedent for smallish Titans. As far as I know, any creature with the "Giant" creature type is elligible to be called a Titan and Giants are traditionally 3- or 4-power creatures. I'll see if I can come up with something besides Seismic. "Earthshaker" sounds pretty bland to me and "Hammerfoot" makes me think too much of "
hammertoe"