The video presentation is certaily top notch. One thing you have to decid is US only or other as well. It would make sense to just to US to start and then branch out reusing the same patterns. For me to use something new I'd need the following:
Formatting of the pictures I upload (standard size obverse/reverse with an ability to zoom)
Data kept in the cloud (web and mobile access)
Easy to add data
Pricing data available in the tool
Availability of the standard numismatic information (size, composition, designer, description etc.)
Checklist, Want List creation
Inventory ability with security to hold purchase information