Very interesting finds there, I'm actually quite surprized that FD has programmed these planets to be irregularly shaped. I wonder if that is inherent in the procedural generation model as a "threshold" where a smaller planet will develop that way, or if it's an "override" they programmed so that the procedural generation model will always give a smaller planet some "irregularity". I suspect that for simplicity it was simply programmed as a stochastic "all or nothing" property rather than a deterministic variable that gradually changes as a planet's size changes. Sort of how Earth-like worlds are "generated" with a "landmass" property while Water worlds have only water, with nothing in-between. I'm actually quite interested in these types of planetary properties (particularly on worlds with life) as I've found the limits and flaws in the procedural generation system to be quite surprising at times. I've found from studying the planetary properties on my exploration trips that the process is much less "random" than you might expect.
I have been on several gas giant moons with surface gravity as low as 0.03 g, they have typically been ice worlds however. The surface gravity calculations in Elite can be rather surprising at times because of the planetary properties that can give planets quite substantial differences in terms of their composition. Some metal-rich or high-metal content worlds can be surprisingly dense for their size and the planetary properties even list certain worlds as "100% metallic" which is obviously not possible given their size. I consider this a "bug" in the planetary generation but it is probably "working as intended" as FD probably programmed the procedural generation model to produce these unrealistic results without realizing that a 5000 km diameter planet is simply never going to be 100% metal (they also have quite a few bugs with the atmospheric properties as well but we can't land on planets with atmospheres yet). As a result these larger metal-rich or high metal content worlds often have higher gravities, such as the ones in the Deciat system with around 1.5-2 g. The larger ice planets in contrast can actually still have moderate surface gravities because of their size but most of the smaller ice planets around gas giants are both small and not very dense, which is why I've seen 0.03 g fairly commonly on those planets. Driving the SRV for mats on the 0.03 g planets (which for some unfathomable reason are often listed in Galnet as being good sources of selenium) is actually rather amusing because it's actually your SRV's thrusters, and not the surface gravity, that provides most of the "downforce" that keeps your SRV on the surface allows you to actually drive around. When you shoot rocks for mats however they take 10-20 seconds to fall to the ground on these planets because the gravity is so light.