After the market goal for Yi 4k + action cameras

I have a Yi 4k + action camera and I am about to go on holiday abroad. I want to replace the standard lens which, in my opinion, is 150 degrees POV because it has too much distortion.

Pixaero manufactures lenses after market. But I have trouble deciding which goal to buy. The website strongly suggests a 3.4mm lens, which equates to an 18mm focal lens. It still seems wide. Although the lens claims less than 0.5% distortion.

I thought that their 6mm lens would be better with a 35mm focal length.

I know that the first goal is good for the landscape and the wide scene. But what about the middle distance and closer. The other problem is that the objective of 3.4 mm is 30% more expensive.

I used the standard lens to try to take a picture at an air show, but the plane was not bigger than points in the air . Will the 6mm give a good video in all ranges? Does the 3.4mm really have such an advantage?