How about any of these? I know there have to be other options out there - can anyone recommend something? LiLY CoW 5!!
It provides the ability to write scores with tab or standard notation. Its easy to work with but still obtains everything that you may want such as dropped tunings, just to name one out of the many others.
Have a software recommendation? Launching the app, you'll see a fairly basic interface without any clutter to get in the way. It would make it the best app for guitar tab writing.