How to adjust a correct size of the visual planet texture :/

[rpsnwr]

Hello, while learning the planet editing, I'm wondering how to adjust a correct size of the visual planet.

it sometimes looks like this.

and sometimes looks like this.

size and radius:
visual planet radius: 15000
texture size: 610x297

this planet pack was based on Mario's "Earth Overhaul Official 2".

is it possible to calculate or something? :/