I'm not sure Stencyl
fits here since I haven't really figured out how to use it but there has certainly been card games done on flash.
I think free rules card games are often gameable so design wise, it's probably much better to focus on advanced tactics than actions but I'm mostly talking generically. It would still encompass action but this way it would be easier for a developer to be warned where their game is leading up to. (Does it increase rushing, stalling, etc.)
I know the above can probably be fixed by advanced rule testing but I see it more as a critical perspective because it can define many things. Take the zone of say poker. It's all in there in front but the ordering of who goes first is such a critical moment that zones alone could be what has kept card games limited in reality and in many ways in most software card games with less emphasis on reality. The breaking away from zones then may then allow for a concept maker to accidentally or purposefully create a card game that's altogether much more different and balanced.