When you say you've spoken with some galleries, did you meet the owner/curator? For me, this is a big part of the equation. If you're going to be giving 50% or whatever of your sale to someone, you want them to be professional and have a vision for selling art. You also want to like the cut of their jib, if you know what I mean. Check out their social media, the ones with the better social media game who make high quality posts with very few spelling mistakes are likely going to be more successful overall than the others (this isn't always true, some galleries manage to be successful while eschewing social media, but they're usually big-name big-money places with established high-end clientele). Make sure you're a good fit with the other work in the gallery, you want to find a balance between being unique enough to stand out from the other work there, and being similar enough to the other work that the people who walk in or frequent the gallery and like the work there have a good chance of liking yours as well.
Also, alot of the time you don't have to pick just one gallery. It's generally a good idea to spread your work out and avoid being in 2 galleries in the same city however. Some gallerists really like when you give them some sort of regional exclusivity and will work harder to push your work out the door if you agree, but you want to be very sure you're a good fit for eachother if you're doing something like this, unless you've got things going on in another region outside their proposed exclusivity range.
First impressions matter. If you've got a wierd feeling about the gallerist or the gallery in general, there's a reason for it. There's always a little nervousness upon meeting for the first time, but if you feel any red flags or little doubts in the back of your mind, there's probably a reason for it. Not all galleries and curators know what they're doing, and their success may be attributable to location or something else instead. Not necessarily a bad idea to be in a gallery if this is the case, but I find these kind of galleries tend to push themselves more than they push their artists' work, or have a tendency to want a particular type of piece from you rather than just giving you freedom to create what you want for them. That doesn't mean they can't do a good job selling your work, it will just be a different experience than a gallery that is built up on the skill, connections, and know-how of the gallery staff.
Location is an important consideration, but isn't always the best predictor of gallery success. You have a higher chance of selling to someone in a busy city centre or tourist trap kind of area, but it isn't a silver bullet that guarantees you'll sell work there.