NP4:
Snapdragon 8 Gen 5, LPDDR5X, UFS 4.0 (Yes, Nothing won't use the most powerful processor to reduce costs, but 8 Gen 5 (non-Elite) is undoubtedly a very suitable choice.)
A battery around 6500mAH (silicon-carbon batteries have proven their strength in the hands of crazy Chinese manufacturers, but limited by the Nothing back design, 6500 is believed to be a possible value)
Stick with Glyph Matrix and expand upon it, with a rear screen similar to that of the Xiaomi 17 Pro.
A slightly smaller, customized screen (the border don't need to be narrower, but a more balanced screen will be available, around 6.5-6.6 inches in size). It will support LTPO and ultrasonic fingerprint recognition.
65W charging is sufficient, but its sustained performance needs improvement. The current NP3 charging speed degrades too quickly.
A 1/1.3-inch main camera is sufficient, but the periscope telephoto lens needs optimization, as the current sensor is too small.
A larger vibration motor and better sound quality speakers (yes, this is important, especially for improving the everyday experience).