It's really well done. There's a lot of unusual solutions to things. I've fully automated my bathrooms to clean waste water without using any automation or fresh water. Super efficient closed loop that actually produces more water than it uses.
Stuff like that makes the game worthwhile.
Its really a brilliant game, as so many of the KLEI Entertainment titles are, I have several hundred hours played on ONI now and like you say there are so many solutions to things, yes you can look around on the web and find things to build but the sheer scope to come up with methods of your own is huge. The physics and science behind the game mechanics, whilst not 100% accurate, are close enough that you can come up with very realistic systems. The closed clean water loop is a great system and I use something similar (I also use a closed loop system for producing unlimited quantities of polluted water) , once you can get closed clean water and closed dirty water running and then get a system set up for producing unlimited quantities of oxygen you have a good foundation for getting started on rocket building