What he said!
I can see the functionality of a clock for example, but would I want a alarm clock? I can see the benefits of being able to view documents, but would I want to be able to edit them? Personally no.
Maybe I'm a bit odd as all I want is a good, solid ereader with great 'reading' functionality, easy to use, a great screen and long battery life so the only things I would want to add would be to enhance my reading experience.
But if you want an alarm clock that plays the national Anthem at hourly interviews, whilst showing a gif of your National flag, whilst you complete your accounting spreadsheet, whilst listening to your favourite tunes, whilst checking your emails and viewing your photos then who am I to argue........I just want to read.