I use my Tab all of the time to write emails... Just get a good "split" type keyboard. I have been using "SwiftKey Tablet X" for a while now and love it. The layout is done so that you can hold your Tab in your hands and reach all of the keys with just your thumbs.
Here's a screen grab of it split:
And the other nice thing about SwiftKey (and i assume other 3rd party keyboards) is that you can switch back to a standard keyboard on the fly.
Here's a screen grab with it set to standard:
Hope that helps you out.
Sent from my Galaxy10.1 TouchWiz/ADWex equipped Starship.