Well, the tandem of crypto currency and gaming industry surely is exciting since there are many gamers in different country. But I think, the bitcoin should not be use for payments only or to buy items and/or peripherals in the game. I think there should be atleast other game wherein they can get bitcoin, maybe the best is the gambling but a pvp type of game.
That is possible too, actually the author mentioned like a battle royale game that you earn bitcoin when you hit other players, and vice versa.
This new platform, gaming, is very useful for spreading bitcoin, and is actually one way we can invite gamers that are nonbitcoin users, surely they will be interested. Not only that, bitcoin could be mainly used as a payment method or the main currency used in online games. Not bad. I am sure gamers will agree to this one.
This is a great idea for a game. However, often times PVP type games where the ones who are the ladder are the ones that get rewarded is a double-edged sword. And oftentimes they cause more detractors in the game than help. PvP leaderboard type of games causes some form of demotivation to people who are not in the ladder, they tend to quit because they know they don't have any chance of getting to the top anyway. On the pther hand, this type of game are usually the ones that breeds hackers. So just ensure that the mental state of your players are kept in check along with you code the game to avoid unfair advantages and you should be good.