I assume the map generation algorithm has a lot of randomness built in. I also have had widely differing results with the same settings.

But that doesn't bother me, I like to be surprised

I have seen it mentioned in other threads that abundant settings can count against each other in a manner of speaking. If, for example, you have abundant asteroids then there are less opportunities to have systems that can have habitable planets. Since there is indeed a large amount of uncertainty fudge (to borrow the phrase from another thread) for each setting, it seems like there is a wider variance in overall map generation than some people enjoy. I personally have modded in additional habitable planet systems (using instructions from other threads) to make the starting position feel less isolated. I have also experimented with varying combinations of common and uncommon settings along with abundant planets.

I've been saying this since just after release, they put a hard cap on maximum planets, I'm not exactly sure why other than some type of performance hit.  This is, however, why if you play smaller maps with abundant settings you will see more compact star systems (full galaxies) with good planets around many of them.  In larger maps, gigantic and above you start to see the galaxy emptying out and planets becoming less common even on abundant settings.  I've asked to no avail for them to re-consider this and to take another look at the larger map size settings and the answer to those requests are like the answer above, one has the ability to mod, which doesn't help those who either don't mod or don't like to mod the base game as for some this opens the opportunity to cheat (even though one can cheat in other ways).

more spambot BS...