Lens recommendations for travelling the USA

I'm about to go travel around the USA for a few months. I'm a complete noob at film photography but I have recently had the seals etc replaced in my mum's old fg-20. Unfortunately the lenses she had (a 50mm 1.8f and a 28-200mm) are no good due to fungus and scratches on the lens.

I've bought a 70-210 (second picture) and am looking for recommendations for a second, probably prime, lens which I'll keep on the camera as my main carry around lense. I'm tempted to get another 50mm to replace the one on the camera but wonder if a 35mm might be a better balance option for landscapes/streetscapes where I want to fit a lot in the frame.

What sort of lens would people recommend? Keeping in mind that budget is not huge and the camera not fancy.

I'm more interested in shooting things than people fwiw.