Have you considered changing the concept of the game into something similar to the SAO or Hack type of playing or maybe an Oculus Rift based, or fully virtual enviroment. I think it would make the whole deal more serious and interesting than it is now since the dude is literally just sitting there in front of a screen and pressing buttons on a keyboard. I think a change of concept would make it more intense and would give it more appeal.
Now this is a concept that has been adopted by a few manga out there and that worked out quite well for them. One of them is most notably my favourite anime/manga Yu-Gi-Oh! wich at first focused on all sorts of games through wich the protagonist fought all sorts of criminals and wrong doers, and then changed the focus to the game of Duel Monsters after many requests from fans. At first the game was played much like yours, in a realistic ways of player sitting next to each other by the table and played cards while the holograms would appear around them through projectors. Later they advanced it to make it more attractive and intense by giving the characters devices called duel discs so they could fight in a lot cooler way. So the point I'm trying to make is that a change of concept would be a good idea, especially since the comic is in it's early stage, so the audience didn't get attached to anything specific.
