We are engineers. That means we solve problems. And there ain't a lot of problems as engaging as the need to counter some kind of threat.
Premise
Question of base defense mechanics has been raised multiple times(be that here or on Reddit), which shows that there are a lot of people that do not really enjoy current state of constant peace in the game world. There isn't much need to expand because of overabundance of resources. We can build our factories in any way our creativity/laziness allows us, it doesn't really matter in the end. Efficiency can be a concern, but even then nothing stops us from just leaving game running over night to stockpile resources instead of improving/expanding factory. Besides that(correct me if I'm wrong) currently we can literally wipe out every living being on the map and be left in this beautiful but dead tourist resort alien planet, which isn't as difficult to achieve as you may think considering we can have several players doing hunting.
As you can see these things as well as absence of risk do not contribute to prolonged and engaging gameplay. But the moment we have to account for a constant threat of any kind, doesn't matter how big or small, every aspect of base building gets much more depth. Factory layout, terrain topography, supply lines, a lot thing suddenly begin to matter. Not talking about weaponry itself. Who doesn't want to see up close and personal how minigun turret they built is raining bullets on enemies?
On other hand there are people who do not want some stray hog wreaking havoc in the middle of megafactory they spent 50 hours building. Which probably is the main reason why devs opted not to add alien attacks yet. Which is totally understandable. They don't want to please one camp of players at cost of annoying another. So here is a possible compromise solution to this problem.
Proposal
Game map is already split into several distinct biomes(grasslands, desert, jungles etc.). Which means we can treat of them as separate zones. And apply different rules to some of them. Like to keep starting zone safe, but make other zones(all or just some) hostile.
At same time give player convincing reason to go and exploit distant zones. Like unique resources, similar to how uranium ore is currently implemented. Anything that makes player want to build if not small factory but at least an extraction outpost out there in the wild. And since we have to fight our way through to get there(even in current state of the game) it should feel natural that we also have to somehow defend these outposts.
This ensures that player is safe until he is ready to boldly go where no construction tool has been before. Doesn't have to worry about too much things at same time, especially in early phases of game. Can venture on long exploration trips because he doesn't need to babysit his main factory. But can't be completely careless later down the line.
TLDR;
- Starting zone stays safe.
- Other zones contain unique late-game resources.
- Aliens attack only those distant zones.
I encourage you to voice your opinion on this topic so we can properly discuss it and see what people actually want.
Also you can vote in Satisfactory Community Feature Requests channel here.