First off, awesome game! I enjoyed what I played of it and think it has so much potential and a great aesthetic. I will be keeping an eye on this and look forward to seeing how it expands in the future.
Bugs
1. I launched the game from itch.io app. I used the "Maximize" button on the Windows interface of the game window to full screen it. Then, from within the MewnBase options, I clicked fullscreen in an attempt to make it borderless fullscreen. At this point the game crashed without any error given. I tried to launch it again from itch.io and it kept giving an error. Closing and relaunching itch.io didn't help. I was able, instead, to launch it from the .jar file in the local folder. I preserved my world and save data by copying the world folder into the game folder (contains the .jar file).
2. I crafted an RTG and placed it. A few minutes later I accidentally let my space kitty die and had to load back into the game. My placed RTG was still present due to automatic save from a new day. However, I still had the same RTG in my inventory and was able to put it into storage and also place it in the game world. I believe the RTG was the last item I placed before dieing. So, it would seem that by dieing and loading in the same session, I duplicated the RTG I had placed.
3. I noticed some... artifacting? during gameplay. There were glitchy black lines that showed up. Perhaps were tiles meet? I have some gameplay footage below that it shows up on. I use a 4k monitor, but it was in 1080p. The black lines don't always appear, thankfully.
Feedback
1. I'm sure it isn't a priority, but simple ambient background music at some point would go a long way.
2. Some way to show how much power each module is draining. I haven't used the Power Switch yet, so I may be missing that functionality if it exists. Maybe mousing over the base module or having a hotkey that will open Base Statistics to show what each module is doing (even if you are out exploring?)
3. Reasons to explore. I didn't feel compelled to explore because it seemed like I could get everything I needed right around my base. I read that you'd like to implement more varied biomes in some form, which would probably help. Additionally, having randomly generated structures/points of interest to discover/loot would add interest. Also, if you expand on rge crafting and create more complex items there could be more rare components that can't be found near the base - forcing the player to branch out and explore more.
4. Damage indicator on the vehicle. This isn't entirely necessary due to the smoke effects you have. However, a way to gauge how much damage the vehicle has taken and a way to repair the vehicle while away from the base would be nice. Again, maybe I missed this feature. My car blew up before I could get out and try to click on it.
5. Split stacks of items when storing them/removing them from storage.
6. I'd like to see workbenches and smelters allowed inside the base. Or did I miss this functionality entirely?
7. "Inventory Full" when trying to craft an item that will use resources in my inventory (therefor, freeing up space) drives me nuts. I understand from a coding perspective this may be a challenge. From a gameplay perspective, I am hoping that if I am crafting an item that uses exactly the amount I have my inventory it won't say "Inventory Full."
Overall, I love it. The content, currently, is fairly easy to get through. I think if I were to play the Endless mode I would be able to breeze through a lot of the items. The more challenging part would be accruing all the resources needed to get a really nice base with plenty of energy put together.
Gameplay