When VisiCalc hit the scene back in the eighties (in the last century), the relatively small group of Apple II users went crazy. It was like manna from heaven for the poor accountants, scientists and engineers who were used to filling in enormous analysis sheets with a pencil. Now, they could use VisiCalc to do the same task, AND calculate the result automatically.
Inconsistent data : This becomes most apparent when trying to find a particular record or cell, based on the contents. If a space is incorrectly added in the wrong place, the search or filter fails.
You'll need to develop good marketing material. Things like demo videos, which you can find plenty examples on YouTube, screenshots, and keyword rich descriptive text help people find your spreadsheet and communicate the value that sets yours a level above the rest. Excelville.com actually allows you to upload your spreadsheet with all of this marketing material in an easily searchable and user friendly website.
Many spreadsheet applications nowadays have functionality above and beyond the traditional, offering a variety of charts, look-up tables, databases and more functionality than can be mentioned here.