A mechanism that I feel space exploration (SE) implements in a really interesting and unique way is trash/byproducts in space. I think this is an interesting design space for mods and perhaps the expansion.
The way I see it, a byproduct from a single recipe is to first-order just an output, except that (1) it is a type of product you probably already have and (2) you tend to only get relatively little of it compared to the main input/outputs.
This means handling byproducts tend to just increase the spaghetti/risks of congestion of your factory and it is clear that from a practical perspective the effort in trying to use the byproduct is often not worth it. As a consequence, single byproducts from single recipes lend themselves to be put in boxes/voided if possible, which is aesthetically unpleasing.
Single recipe byproducts are therefore a bit like an input (i.e., they require you to run a belt or something), but at the same time just more annoying. I think this is why vanilla/many mods tend to focus on the input side, i.e. make the web of inputs more complicated/deeper, and keep the outputs relatively simple. It feels more 'fair' and gives a better sense of progression (I managed to make product X, and as long as I supply inputs the process will not stop).
What I feel SE does differently is a combination of three things:
- Firstly and most importantly, there are many recipes that produce the same 5-6 byproducts (scrab/contaminated scrab, new/used/broken data cards, and to some degree empty barrels). These can therefore all go on a single 'trash belt', which is run in the reverse direction of the bus to a 'recycling center', where the products are recycled and added back to the bus.
- Secondly, some of the byproducts are fairly valuable (fresh data cards). It is clear *these* at the very least should be re-used, and once you are getting into the business of running them back to where they are produced on a belt, you might as well add the other stuff -- in other words, it is a mechanism that is easy to discover and then expand upon.
- Thirdly, handling byproducts (the recycling center) is itself in my opinion an interesting setup that can be optimized/upgraded over time. I am finding it fun and unique to build using splitters/buffers, and I think it is fun to look at when it is running; most of my factory is just full slow moving belts with stuff, but the trash center is constantly sorting and recycling trash. I can even get an idea about what my factory is doing by looking at the color of the trash!
Furthermore, it means that actually handling a byproduct when you set up production is no longer frustrating (just run it to the trash belt on the bus), and therefore byproducts don't feel 'artificially frustrating' the way that e.g. getting a bit of water out of a process that requires water as input does. It also means that working on the recycling center (upgrading it, scaling it up, etc.) is much more rewarding as you know that upgrading it will benefit all of the factory.
Liquid byproducts are a bit of another story, as I at least am still handling them 'the traditional way' by running each of them on a fluid bus. I am thinking if there is a way to do something more interesting, for instance by mixing fluids for later de-mixing, or perhaps by letting some buildings require empty barrels as input and produce waste in barrels.
One last thought: I think there is an interesting logistic possibility in giving the player an option to send 'space trash' back to a planet for much more efficient processing, vs. keeping it in space and doing less efficient processing.
