You need to do major market research in your area in order to figure out of there's any real desire for such a thing. An idea is great, but if there's no customers to back it up you're just going to end up broke.
A major problem you'll run into is that you'd need a tremendous amount of space if you intend to host league tournaments, you'd also want to be in a heavily populated area, meaning someone else probably already had the same idea, you need to compete with prices online for MTG cards.
Back before Amazon was a huge thing you'd go to stores like that to pick up your cards all the time, however now you can buy 3x as many cards for the same price online with free shipping to your front door so you don't need to even bother with the gas.
Furthermore most people have their own consoles anymore so they're not going to want to go somewhere and pay to play something on the spot (I assume your plan is to make them pay for playing the consoles in the store) when they can just go rent the game for chump change or maybe they have a gamefly subscription.
I had a friend whose father went balls deep trying to do the same thing and just wound up broke within a year and a half because the market wasn't there, and frankly he didn't have the parking for it even if the market did exist for his business.
I'm actually in real estate so believe me when I say that rent is more expensive than you might think. The space you'd want not even with anything built inside of it other than the basics (walls, electrical outlets, HVAC, etc.) around here (and we're pretty cheap in my area.) would run you about $6-10 per square foot and you'd want around 5000 SF to start, which might even be on the small side to be honest. So you're pushing 30-50k per year just in rent. Add to that your overhead expenses because your electric bill is going to be through the roof with just running all of that stuff and the AC you'll need to keep the place tolerable with all that heat being given off from the electronics especially if you're hosting a tourney.
Don't get me wrong, please don't think I'm trying to take a giant steaming dump on your idea, I just want to provide you with some realistic perspective.