I would try with a bit of flash for specific captures, might give you the sharpness/perceived sharpness you are searching for or better yet search for the light.
Unfortunately, posting a 1066px × 1599px is not going to show much when it comes to image quality. At that resolution, the image looks very sharp and the scene has a lot of contrast (too much, in my view), but that's what hard lighting does.
As a DX lens I did like this, and it has a range suitable for being a 'walk around' on such a camera, but on FF it shows its limitations. I would agree that it would benefit being slightly wider, which means looking at the more expensive and shorter range 14-24mm f2.8 Nikkor.
However once you experience the difference, especially on a FF, there are no regrets. The walk-around then becomes the 24-70mm f2.8 Nikkor on the FF. unless you regularly have a need for the wider angle or indoor shots with the benefit of the greater field of view.
Ultimately most lenses will produce better results when not wide open but in the range you describe at f5.6 - 8.0.
Not sure adding flash per se to that high contrast photo is going to be massively beneficial and may create hot spots unless you adopt an approach with a softbox too. It might lose some of the harsh shadows though.
I like my EFS 17-55mm lens for my 7D2 crop format Canon DSLR with two exceptions... 1. It is a bit large in size and I wish it were physically smaller and 2. I wish that the focusing was internal because I don't really like the front element protruding.
But, OTOH, this lens has served me very well all over the world and is a nice travel combination with the EF 70-200mm f/4L IS. I have lately begun to use the combination of 17-55mm on a crop camera and the 70-200mm on a full frame camera, That way, I do not have a gap between the long side of the 17-55mm a d the short side of the 70-200mm.
The spanish isn't the best I've seen this year ...
... no, wait, I think it is, but not for long.
feliz año nuevo
I still have memories of a Nikon ??-55mm zoom kit lens - until then I didn't even know what 'veiling flare' was. (can't remember the exact model, didn't have it long enough ... )
It all depends on what your preferences are. But I think the most important thing what you've to learn is to think of the things you can shoot with the gear you have in your hands, not what you could shoot with gear you don't have in your hands.
A wonderful street photographer, Thomas Leuthard, uses a 85mm prime. https://digital-photography-school.c...-photographer/. Others prefer a "normal" prime just for its size. It are your eyes that has to do the main job.
George
that's the 18-55 af-s 3,5-4.5G ED, Kit lens that came with my D70s, Still have it, its a decent lens for the price, I have converted the D70s to IR since, its lots of fun to play with..