From my experience, removing the factory screen protector tremendously improved my overall screen responsiveness. If you look closely around the corners you can see it.
Also, the stock keyboard is messed up and doesn't have a user dictionary, auto capilization, or auto insert period with two presses of the space bar.
My favorite keyboard so far has been the Jellybean Keyboard by VLLWP. You can customize a lot of settings such as using the volume rocker to mover the cursor while typing and split the keyboard apart for a differnt typing experience.
You can add your own words to the user dictionary and the auto correct works fairly well from my use of it.