This suggestion is two parts:
Firstly, raiders have a chance of coming to grab resources rather than simply killing everybody. They'll grab a stack of the most valuable resource they can find (anything under the "Resources" heading in stockpile controls, excepting items in hoppers), then leave. It'd take some planning to get them to consider breaking through doors/walls to get at stuff, instead of just being disappointed should the player fort up.
Secondly, raiders with pistols (and I'm saying specifically pistols to save time on trying to decide "what would be an upgrade") will consider swapping their pistol for other weaponry on the ground. Could be untidy colonists leaving gear behind, unprotected stockpiles, or even their fallen buddy's grenades... I'd suggest limiting the raider's consideration to "got within five squares of a different weapon" before he'll change his goal from "fighting" or "smashing things".
Basically these two suggestions are in response to me analyzing my playstyle and realizing I have a pronounced tendency of letting my stockpiles get totally overrun - something which does not currently have a penalty beyond "civilian colonists will go charging into the crossfire to reach the stockpiles".
Definitely solid thoughts; I'm planning on a bit of an enemy AI upgrade with Alpha 3 so some of this may come through then.
Personally, I think raiders should always focus on stealing and/or kidnapping (rather than murder). It just fits the concept of "raiding" so much better. Raiders who successfully steal resources and escape the map could return later, giving players an opportunity to get revenge.
I would also like to see more advanced raiding parties doing things like attacking power generators and destroying power conduits, and even waiting until the batteries have run dry before proceeding further into the player's base.
The problem there comes with how much effort that takes to program. Arguably giving the raiders a goal and a little more intelligence with their raids is a feature of significance right now, but with the current lack of features, a slight upgrade and a goal is all they should have. Making them tactical and strategic would be nice, but I personally think it can and should wait until more content means that need to be more tactical. That's not a dig at the game for having too few features btw, just saying that currently, its a fact :P Alpha is alpha
True, having the raiders lay a full-blown siege against the player would indeed be very complex, but there are lower hanging fruit that we can grab on our journey to "more intelligent raiders"
For example:
- All raiders are now hostile towards solar panels and geothermal generators
- Raiders carrying molotovs are now hostile towards immature crops
- When raiders finish staging, they are given hauling jobs to the nearest resources instead of attack jobs to nearby colonist. If successful in picking up a resource, they then attempt to leave the map with it. They pause to shoot hostiles, but don't go out of their way to hunt them down.