I would need it for sure. When you get to the point where you have so many macros you need all the keys you can get.

And if you are charging for an application I would say fixing the bugs is a must? am I wrong here? Why would someone buy a product knowing it has bugs (although a majority of us play WoW which is full of bugs anyway) when things are available for free that have more utility (basing utility on the alt/shift/ctrl issue).

So yeah for me (and probably 80% of the wow multibox community) those keys are vital.

If you really want to fix it make it free and open source or at least make it free and take on a partner to fix the bug and possibly charge after that. Although with free open source software like synergy and multibox available I do not think charging should even be an option at least if you are aiming to get business/feedback from the WoW community.