Full disclosure: I haven't actually played the game other than testing that editing the data files work. I plan to, but haven't ♥♥♥♥♥♥ around to it yet, so some of my game-specific knowledge will be lacking.
I have been playing it for a while now, and have been using 90 second hours. 48 seconds definitely felt way too rushed, especially when running the blacksmith and needing to keep up with stock demands.

I came across this after looking at a negative review for the game that complained about the in-game time passing to quickly for their liking. So I took a look at the game files and found that this (among other things) are easily configurable.

1. Go to the folder where the game is installed. Something like C:\Program Files (x86)\steam\steamapps\common\Kynseed. From there you will see a Data folder, in which you will find the file Config1.xml.

2. Right click on the file and open it in your preferred editor. Something like Notepad++ is ideal, but opening in the standard Windows Notepad will also work.

3. Don't worry about the XML syntax if you are not familiar with it, although it's quite simple and easy to learn[en.wikipedia.org], we're just going to be making a very simple edit. First, locate the key SECONDS_IN_HOUR_GAMETIME (ctrl + F to search -- although it should be near the top of the file).

4. A few lines underneath the line
you should find
which is the value for that configuration key.

This means, by default, one in-game hour passes in 48 seconds. Change this value (48) to whatever number best suits your play style. Personally, I like 60 seconds per hour, so one second is equivalent to one in-game minute, but you can use any positive, whole number you like.

5. Save the file (ctrl + S), close the editor, and launch Kynseed. Even when loading an existing save file, you should notice that the in-game time now moves at the rate you specified in the XML file.

There is also a file called Config2.xml which has different values for the same keys, such as 20 day seasons and 25 second days. Having only played the game for a few minutes, I'm not sure if at some point the game switches to this configuration. If that's the case, you will want to make your same changes in this file as well. However, if the whole game uses the same configuration as the prologue of 14 day seasons and 48 second hours, then you only need to bother editing Config1.xml. Update: Have been playing for a while now, though still in my first generation, but haven't run into any scenario where the other configuration would apply.

Anything in these configuration files within the Data folder should be able to be modified in the same manner as the directions above. But since this isn't an extensive modding guide (nor do I have enough knowledge of the game to provide such a thing), I'll leave it to those who want to investigate what else they can change to their liking and/or release their own thorough modding guide.

Hope that helped!