They had to rewrite SFS - I get it.
So why not to publish optimized version to community as 1.4x and then each week/month publish new feature? This way people would have more fun from the game. It's really really annoying when you have to wait and you don't know if you have to wait another month or year...
I don't think a monthly update would be suitable in practice. This is actually way too short to implement significant features, as Stef has to code them, beta testers have to test them, Stef has to debug... You'd be surprised to see how time-consuming is software development.
Such frequent updates would mean that he would only work on small features, like new skins, a slightly different interface, maybe if we are lucky a new planet (probably not a whole planetary system like Jupiter and its moons though)... Only things he can deliver within one month. The good side is that he could fix some bugs indeed, but in the end the game would never evolve significantly.
I understand the will to play a new version, but such frequent updates wouldn't be a sustainable rhythm for Stef.