the idea might be valuable (simplifies people's work), but you probably want to avoid eating the huge market of business cards. There are dozens of them. Plus, you may want to validate your idea first. I'd be cautious about the fact that customers are ready to have the same template than others when they call a designer. :S.
Other than that, I find the idea seducing
About validating my idea, it's what I am trying to do, quite a tricky task :/. Any advices on how to do that would be really appreciated.
Find your customers first. If you know who they are, then you've got a chance to validate the idea. If you don't, then you can't.
Your customers will fell like they are modifying template, but behin you are doing the job yourself. :) You could set up some taskrabbit stuff for that.
In your case, I would also go to customers as soon as possible to avoid doing something that wouldn't match their needs :).
Good luck, and keep us updated!
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