I tend to disagree with this comparison to bitcoin getting it's foothold thanks to gambling justification. That was a LONG time ago in Internet years. this is a new age now, filled with far more regulations that have caught up. The average Internet user is more sophisticated now compared to back then.
I understand the economic benefits to some people with this... but if that is what we have to show front and center in a showroom, then the real magic of bitshares is going to be lost and detracted from.
We need more user cases. We need success stories in the ecosystem. Everything is so new and everyone expects it all to just take off overnight, but that's just not how it happens. There is a tipping point.. and as we keep on bringing on useful things that compliment the DPOS ecosystem there will come a point where it just takes off and discussions like this will not be held in the light of being some kind of Monorail savior to bitshares.
Lets be frank though. This is not something for bitshares to develop anyways. If there is a 3rd party gaming entity that wants to use the bitshares platform for their transactions there is nothing stopping them. So for all those pro-gamblers, instead of just talking about it here, you could be reaching out to various gaming places that currently user bitcoin.. include your refer id! talk with them about how they could get first mover advantage.
For OPs proposal.. sounds like a great third party project to pursue, but the client is not where it belongs. You got plenty of other channels to utilize for advertising and for the game to work through your own client or web based. If it's to be distributed, yes, it would involve running a DAC.
At the end of the day, putting a slot machine right at the same counter where you go to get your banking or investments done is just so disassociated from anything anybody has ever used it makes no sense... unless we are now making the wallet for the purpose of scooting into the casino to gamble... then thats how most will perceive this to be.