Top lightweight prime lens for Nikon Z6 during travel?

Unfortunately, I had issues with these options:

• Nikon NIKKOR Z 28mm f/2.8: plastic build quality felt cheap.
• Nikon NIKKOR Z 40mm f/2: corner sharpness was disappointing. Neither met my expectations tbh.

Just found this thread and felt like I should mention a few safety things since youre heading to a crowded place like Tokyo. Since you found the standard Nikon pancakes a bit lacking in build, you might want to consider some of the third-party metal options, but you really have to be careful with compatibility. I would suggest looking into the Viltrox AF 35mm f/1.8 Z. It is usually priced around $350-$400, which is well under your budget. The build quality is actually quite robust since it is mostly metal, which feels safer than the plastic kit primes. However, you should definitely check the official Viltrox website to ensure you have the latest firmware installed before you leave... third-party autofocus can be a bit finicky on the Z6 if it isnt up to date. Another technical detail to keep in mind is the weather sealing. Tokyo can get quite rainy, and some of these cheaper primes dont have the best gaskets. If you want more data, I always check the technical charts on Photography Life or the side-by-side comparison tool on DPReview before I buy anything. Make sure to test whatever you get for at least a week before your flight to avoid any surprises. You might also look at the Viltrox AF 24mm f/1.8 Z if you want a wider perspective for those narrow Shinjuku alleys, just keep an eye on the lens flare. Be careful with how much you carry tho, even small lenses add up after ten miles of walking.