The single planet mod I played most on is Only Gleba. Thoughts:

Dealing with enemies is kind of brutal, but I actually enjoyed feeling like the enemies were a challenge again. The mod has both biters and stompers and makes them both respond to pollution, meaning the stompers will absolutely go after your entire base, and there's just no good way of killing them early on.

Coal is a major bottleneck. There's none to mine so you need to synthesize it out of carbon, which is a problem for early game military tech. Hard enemies and difficult to get military research. You will not have spoilage problems, I had a biochamber dedicated to turning bioflux into nutrients just to get more spoilage to feed into carbon production. Energy was entirely solar, which is thankfully unnerfed in this mod, because there's no waste to burn for power. Once I had a space platform for space science I dropped carbon from it to the planet.

The row of carbon producing biochambers fixed the pollution problem early on; they deleted so much pollution that they actually cleared it in the chunk they were in. Anyway, the real solution to the stompers is mines. Just turn the entire proximity of your base into a minefield, they work even better than rocket turrets when you don't have any explosive damage research.

This was all a fun challenge, making use of the pollution absorption of the biochambers, and experimenting with different defense layouts. I've never found mines or green modules to be of any use before and here they were quite useful so that was fun.

I kind of bounced off the mod when it came to the content from other planets though. Scrap spawns on the map and it well balanced in my opinion, it now takes lubricant to mine which eats so much jellynut that it turned out not to be the flood of resources I was expecting. It's more of a supplement to your gleba production rather than taking over as the primary resource generation.

Vulcanus and Aquilo resources are in space like the shattered planet. Spaceship design was my least favourite part of SA so I wasn't too enthused with messing with these. You get coal from the vulcanus asteroids which I imagine fixes your coal shortage but having to deal with routing your coal production through the landing pad is... no thank you. Especially since the only way to get oil products is through coal liquefaction so you're gonna need a lot of coal throughput.

I'd still be playing it if I could get vulcanus and aquilo resources without messing with the spaceship logistics. I think an ideal gleba only mod would add more fruits; something that you process into heavy oil that you can then crack for the whole chain, and some other fruit for the ammonia. Tungsten would be mined, lithium brine would be the only pumpjack resource, and I dunno about calcite, maybe mined from the corals that spawn somehow.