Is there any working implementation of Google Docs on Honeycomb?
There was a recent (around 5-Oct-2011) update of the offical Google Docs App, with the following changes:

What's new in this version:


Optimized experience for tablet users, Honeycomb (Android 3.0+)

New 3-panel interface for improved browsing
Details panel showing a thumbnail and sharing information
Improved sharing experience with autocomplete system
Landscape or portrait mode

Improved video playback




Maybe it fixes the problems you described. I am sure Google will further work on the tablet compatibility of the Google Docs app, it's just a matter of time.