When it comes down to it, the beauty of 'table top rpgs' is that with theater of the mind you can run the game about anywhere. With how good digital products are of late, provided you have your character sheet and dice - both of which can be on your phone - you could legitimately run a game of D&D in a car driving across the country. Now, I'm not sure if I would recommend that - especially if the driver is the GM - but you could.
That said, in my experience there are some things that qualify a space as a better gaming space than others. Obviously your mileage may vary when it comes to what works for you and your group, but these are some things you want to consider.
While gamers in a crunch can keep everything on their phone and make it work, in my experience games take up a lot of table space. Character sheets, note paper, and dice tend to spread out. If you use battle maps and miniatures they need their space too.
All of this without even mentioning that most games will need space for food and drinks. Drink bottles and bags of chips can sit on the floor when not in use but not all beverage and food containers can do that, especially not if there are animals in the location. Not to mention the people themselves are going to need space.
It is one thing to squeeze in close to other people for a short meal or in the winter. It is another to be sitting cramped around a table for a 4-6 hour gaming session in the dead of summer with an inadequate AC. Yes, you can do it. But if you have the option to not do it, why subject yourself to it?
Sturdy, Comfortable Furniture
Along with the table space adequate chairs that are sturdy and comfortable are good. Gamers come in all sizes. Yes, the stereotypical gamer is heavy set and that tends to increase with age. No, the barbarian player being fat is not a reason they should have to be uncomfortable for the whole game - unless you want them out of the game, in which case just tell them don't try and chase them out.
In my experience chairs are always going to be hit or miss. They don't need to be custom tailored to the group, but sturdy enough to hold the person they have to hold without being too uncomfortable is a big plus. This is also where space comes in. As a tall person I can deal with a lower set chair provided I have some room to stretch out or stand up without bugging people. Without that, and I'm going to need to spend time away from the table just for my limbs' sake, and while I can pay attention while standing a bit away I'm not going to be as focused as I would be at the table. How can I be when I have literally just stepped away?
Simply put, over 4-6 hours with drinks and snacks someone is going to have to use the bathroom. Not to mention the bathroom is the time honored GM retreat location when we need 5 minutes to think about just how the world is going to react to the PCs taking the magic hammer that fixes anything it strikes, and slamming it into a soulless undead horse because science.
Bathrooms should be servicable, ideally clean, and useful. Ventillation is often a good thing for bathrooms in general, but with the snack and soda diet around many games it can be a better idea to make sure you have it. Scented candles can also be a god send should one of the players, or you yourself, tend to leave the place smelling like a truck stop.
A Lack of Distractions
Minimal distractions are ideal to have. Odds are if someone is hosting you are in their living room or dining room, and they may have distractions present like their TV and such. That's fine. It is less fine if those distractions are on and set to distract mode. It can be hard enough drawing people into the fiction of the RPG without having the news going, or someone else playing videogames near by.
This is, again, part of why I really like the private room in a store for games. There tends to not be much in the way of distractions, while all the other needs are more or less set.
Most Importantly: Everyone Needs to be Comfortable
I left this for last, and in my opinion it is the only mandatory thing a place needs. Everyone needs to be comfortable using the space, or the game should not be there. This means everyone in the game should be comfortable going to that place and using the space. It also means everyone else who has claim to the space should be comfortable with those people there. Yes, your housemate who doesn't play RPGs needs to be comfortable with the people in your game being in the house and using the furniture and stuff. And yes, your players need to be comfortable going to your house and using the stuff, even while your roommate is present in the house and going about their business.
If someone isn't comfortable you should find a new location. Otherwise it could end very poorly, and no one wants that.