That doesn't help much.
First, what kind of user interface does the BBC Master use? I can see that it has function keys, but how much does it use them? The best user interface I've ever seen is Coleco's E.O.S. It's quick and easy, no silly icons or anoying hilight bars like the best Commodore programs. you don't even have to press return constantly like on an Apple IIe.
Second, What features are missing? What are the best word proccessor, graphics editor, desktop publisher, database, personal filing system, calendar, personal finance, and spreadsheet? Is there anything these programs should be able to do but can't? Are there any really good integrated packages? What about a web browser?