Hmmm.
How can you type if your palms are touching the surface?
I do occasionally touch my wrist down, but that's just to maintain hand position.
Generally, my wrists don't touch down while I am typing. Maybe that's a characteristic of touch typing?
I think the size would be a factor if the keyboard (spacing between the keys) does not work for you.
I don't find the rMB keyboard to be a problem, as I adjusted to the different feel within a few days. Touch typing is OK, not that much different for me compared to most other laptops (other than those creepy cheap netbooks from a few years ago. Glad that those days are past! )