This picture, and others similar to it, aren't pictures of the woman.

These are travel snapshots, with some landmark and a woman in the same frame.

There's nothing wrong with such snapshots per se. In fact, they're pretty great: they show where you were, remind you of the good times, and they're not anything like the travel postcards you could buy, even though those might feature some of the same tourist landmarks.

But they're not really portraits. If you want portraits, make them about your subject. Watch how the light falls on her, her expression, and what she's doing. If the light and shadows aren't right, move or come back at a different time. If you can find a way to work some interesting background into the composition, cool — maybe she's interacting with it (ideally in a natural way!) instead of just standing there. But if the background and the portrait aren't working together, and you wanted a portrait... forget the background.

For the specific example you give, all of the notes you've given yourself apply — the composition is haphazard, the column is extraneous, the lighting isn't flattering to skin tones. But all of that is really incidental to the basic problem, which is the nature of the photograph as a snapshot.

If you want, instead, to have postcard or coffeetable book photographs of travel landmarks... again, you might want to reconsider. That's been done, and it's best done by people with time to study the site, wait for the right weather and lighting (or make their own). It takes a lot of experience and work. Luck might come into it too, but it's the kind of luck you make by putting in the time. And, you probably don't even want the woman in the photograph.

Or, maybe those things don't sound like what you're looking for. Maybe you just want some nice snapshots from your vacation. In that case, don't worry too much about the photographic merits. They're perfectly good snapshots, great to share with your friends on social media or to look through later. If your model — and presumably your friend or significant other! — is interested, you can spend some time and energy making these real situational portraits. (Plan on at least an hour to get a good photograph.) Or, you can buy photos of the landmark by a local professional or enthusiast, and you can take more technically advanced portraits some other time, when you're not busy enjoying your trip.