I like this game a lot.
Version 0.3.1 is definitely more balanced than 0.3.0. I can confirm that 0.3.0 had issues with game balancing as described by user Namtom below.
I think terraforming can still be improved in 0.3.1. The terraforming options you get are mostly random and many times I find them quite useless, especially if you get several items mixed together (e.g. TNT, fire, toxicity and clouds next to each other). These complex terraforming options usually do nearly as much harm to the landscape as they are helpful.
Many times I wish I could transform that annoying mountain or canyon in the middle of my settlement into something useful. But since you need two to three applications of terraforming for that (e.g. TNT, cloud, cloud for mountains), it takes a long time and is usually not worth to bother .
I believe it would be more fun, if the terraforming items you get on specific days would be more balanced. In the current version, you get quite similar terraforming options each time, i.e. you get three times options with mostly clouds on one terraforming event, three times mountains mixed with either fire, clouds or TNT the next event, three times random sets including minerals the next event and so on. I suggest to make it more even, i.e. you get a set of three clearly different terraforming options on each event. This way you will most likely get the chance to use TNT, clouds, clouds in consecutive terraforming events, which is what you need if you want to transform a mountain to fertile soil. With the current system, you sometimes need half the game to get the right terraforming items to achieve that, which as I said before is not worth bothering then. This I consider somewhat frustrating.
By the way, I have beaten 0.3.1 several times now on hard and once on very hard. I could not beat 0.3.0 even once. I have to admit though, that I usually restart the game several times until I get what I consider beatable starting conditions. The randomly generated maps sometimes end up in the game being unbeatable in the given time (at least for me).
I played 0.20 at least 50 times and found it highly addictive.
0.20 was a much simpler game than 0.3.1 and I am not sure yet which of the both I prefer. Certainly 0.20 was easier to master while still rather addicitive.