Moving around a system or between systems uses the "wait a while while you can work on your base" mechanic. Planets and other POIs are spread out a fair bit and star system jumps take a while as well. I like the idea of you actually traveling through interstellar space, not just jumping to a new region -- makes the world more seamless.
Space POIs are a free range 2D experience that should feel a lot like a space arcade game. Granted the guns and boosts/etc are customizable by other gameplay systems. The main point with this region is disabling the space POI and its defenders so you can board it, or loot resource freighters or whatever.
Space POIs are procedural, using something like ruingen{} to create rooms which are linked together. Like other POIs, ground combat plays a huge role. Outside of whatever your goal is, there's also a heck of a lot of stuff to loot.
Ground POIs work similarly.
Planets use fractalicious and similar engines to zoom in some arbitrary number of steps. Regions that you can land on probably have boundaries because of how the fractalicious engine works (though maybe not if I can make it efficient enough). Because of how fractalicious works, they're totally seamless though. Can chalk the weird fractal patterns up to whatever alien lore I'm going with (created planets?).
Movement on land planets works like it does in other 2D games. Again not sure if I'm using fixed screen, movable screens or a hybrid.
Water planets and watery regions in general require use of a Submersible vehicle. Same deal with Gas Giants and a Gaseoplane or something.
Heavy emphasis on base building mechanics -- your ship is your base and you can pop into it on transit or while orbiting a planet or whatever, and the background around you will change to whatever makes sense. A lot of stuff to cover herein.
Procedural settlements, both on land and in space. Works the same way as other 2D spaces. These are largely only visible from higher zooms -- more populated planets might have some you can scan for and try to reach on foot (or maybe with some kind of Vehicle). Or smaller ones. Bigger settlements are definitely things you're not going to get to normally. I do also like the idea of having a planet that's one giant city somewhere -- it's kind of a space game trope and it would be cool to program it out in the procedural engine.
Crew mechanics as detailed in other games. Simplified a bit and also form-fitted to the 2D space.
Free farming of anything biological whatsoever, with genetics.
It's definitely a resource gathering game. Resources can be gathered in the ways you'd expect:
Rocks and metals are found within caves as befits the tradition there.
Gas Giants, Asteroids and Ocean planets have their own unique resources and those areas take specialized Vehicles to traverse.
Resources can be bought in civilized areas.
Loot that you don't want (or have no value outside of sell value) can be salvaged for materials.
Inorganic resources can be Mined -- a few different mechanics there (including Colonies). You can't build bases outside your ship, however you can totally build Industrial colonies to do the automation legwork for you (or just mining platforms that you check occasionally). Pretty expensive to set one of these up though.
Organic resources
Can be extracted from Plants found on the surface of habitable planets.
Same deal with animals. They move around so you have to shoot them or lay traps or whatever with the physics engine.
Same deal when you fish. On ocean planets you need a Boat vehicle to actually fish with (and the fish are more valuable/useful), otherwise you can just fish by touching a water tile.
These can all be Farmed within the confines of your Ship (or as part of a Farming colony). Genetics are in play here.
They can be turned into other resources -- free alloys or whatever that mix the properties in a Shatterloopian way. Alloys / blended resources do slot into the PGCS.
They're used to create Tools, Fixtures and Modules (which buff various parts of Tools or Fixtures).
They're used to make consumable stuff like food, ammo or batteries.
They're used to create Colonies. Granted you need money as well, but that's more of a legal thing. They're also used to make Mining Platforms.
They can be sold. There's definitely a kind of Economy in play here.
Vehicles are necessary for certain types of traversal, or just when you don't want to take environmental damage / move around slowly.
They require a Hangar on your ship, and also the Hangar needs to have enough slots available for all the vehicle types you want.
Like your Spaceship, Vehicles can be built out in a modular way to your specifications. While traveling on one of them (heading towards a POI or resource pocket or whatever) you can duck into the actual Base here and do whatever you want. Crew mechanics apply as well -- granted crew members aren't living on board the vehicle so their needs there are lessened.
Vehicle Types
Hovercar -- lets you move quicker on land and not suffer environmental issues. With a module they're quite good in Caves as well.
Boat -- lets you move around ocean planets and Fish.
Submersible -- lets you dive into the ocean and explore the areas down there. Submersibles can also be stored in a Boat, with the below mechanics.
Salamant -- lets you (slowly) traverse magma. Using one of these requires that your Submersible or Hovercar *also* has a one-slot hangar, which means that a hangar storing it requires two slots.
In the case of a Salamant stored in a Submersible stored on a Boat, your Spaceship requires at least 3 slots, the Boat 2 and the Submersible 1.
You can move vehicle assignments around easily from within a fixture in your Ship's Hangar. Same deal with moving inventories to your Ship's or vice-versa if you run out of space.
Gaseoplane -- lets you traverse gas Giants.
Astrowing -- lets you traverse Asteroids. There's very probably some kind of fighting that happens here so you might want to equip it with weapons. Additionally, particularly large Asteroids can have a magma layer and so you can store a Salamant within the right kind of one.
More Vehicle mechanics
Vehicles run on Power -- generally it's a rechargeable battery but occasionally they can run on Biofuel or extract energy from the environment, improving their range. You can also just bring additional Batteries with you.
Vehicles are Tethered to whatever vehicle they're matryoshka'd inside. If they run out of power, they dematerialize and go back to their parent, losing whatever is in their cargo. The same thing happens with you, though you do at least keep your Tools/Weapons/etc. This is also an option -- I mean the alternative is being permanently stuck, but if you have some other means of transferring resources you can do that.
The same thing happens if they're damaged too much.
Colonies are sort of a late-game way of Automating resource production. They cost an exorbitant amount of materials to set up, a good bit of money for Legal rights and also Automation chains are driven by Crew members that you assign. They then also need accomodations/etc as well as the overall Happiness mechanic. Assigning Crew members to a colony that are in a relationship (without also sending the other person there) can be problematic.
You can set up Colonies anywhere that isn't just space. Depending on the type of planetary body (planet, Asteroid, gas giant) the requirements will be a bit different, also same deal with whatever the environment is like.
You can also set them up inside Caves or even the Magma layer but there are some ridiculous stipulations for those kinds of Colonies. Nonetheless you should be able to Automate everything in the game, so it should be possible.
If you're moving a lot of product it makes sense to set up Freighters in orbit around the planetary body. They're expensive as fuck (and require a steady fuel source of some kind), but they do offer unlimited storage. You can also use them as a general purpose storage solution because your Ship can only hold so much.
Freighters can also have Shipping Ships (obviously the name needs to be better) that allows you to move shipments of items between Freighters and also Settlements of whatever kind so you can buy/sell things easily.
