Question about RAW on GR

I've just bought a GR, first impressions are that it's a great little camera, though I've not shot much beyond things in my hotel room so far.

I've noticed that when shooting RAW, you can't zoom into the image on the rear screen as much as when you shoot Jpeg, and the preview of RAW shots is also very low res. If you convert them in-camera you can then zoom in far more and see the files in more detail. Is it normal to have such low-res previews of RAW files, and is there any way I can change that in the camera?