if it were a comparable resolution to a lightmap, and all planes were combined at the end, wouldn't it be roughly the same amount of load on the processor?
If it's going to be very small though, this exxageration will work nicely in its favour. I can't say for sure, but I think it will work best with this amount of parts.
It probably won't hurt to go for a 256x resolution texture, the amount of extra detail that you can get will make your character look far better and sharper than it currently is.
chanfan, that looks alot better, only thing that bothers me is the major amount of specular highlights on the characters and the lack of anything shiny in the environment, it makes the characters look out of place to me.