Among the vanilla planets and the modded planets I have played, I've noticed that Apia has absolutely no reason to ever use trains.
The planets resources are available everywhere, royal jelly is obtained right out of the ocean that covers the entire map, and the only other 2 resources (larva/honeycomb) get mass produced once you setup a self feeding hive.
The individual islands on the planet serve no purpose after you've generated enough Wax platforms or landfill to place structures everywhere. resulting in a hyper optimized system where every ingredient needed for everything can be produced right next to where it needs to be.
The vanilla planets each have a reason to utilize a logistics network in order to deliver to the production center.
Nauvis: Mined ores and oil need delivered to production centers
Vulcanus: Mined coal, tungsten, and potentially calcite need delivery to main production.
Fulgura: Mined salvage needs delivered to main production.
Gleba: The Yumako and Jellynut crops can initially only be grown in preset biomes, rewarding the use of trains for bulk transportation for a centralized production area.
Aquillo: Several pumpjack related liquids need shipment to main production area via trains and also coincide with the planets temperature management.
Apia's design feels akin to gleba meets aquillo, except it lacks the logistical puzzle solving that those two planets make you overcome.
Gleba: Resources are infinite as long as the farm keeps harvesting, but each harvest generates spores resulting in pentapod complications. Expanding the farm is only to increase production, as opposed to replacing depleted veins.
Aquillo: Buildable terrain is initially limited until concrete is delivered to the planet, the main logistical puzzle of aquillo being tied to the ship being able to deliver to the planet and survive.
I feel like apia's puzzle is too easily solved, and the planet itself ends up being uninteresting as a result.
My suggestion would be to have the planet emulate fulgora's puzzle more than aquillo's.
Aquillo: You can build anywhere if you have concrete and ice sheets.
Fulgora: You are restricted to building on the islands until you unlock foundations.
If Apia restricted the players to building on the smaller islands, it would allow for more logistical challenges in terms of initial space until the unlock of foundations. The wax platforms could be akin to ice sheets, and only allow certain structures placed on them such as belts.
Additionally, the planet itself needs some biomes to encourage exploring beyond the initial drop point. As of right now, artificial hives can be placed anywhere and it makes it very easy to solve the production for honeycomb.
Instead, make 2 types of artificial hives, a late game hive that functions the same as the current hive. And an early game hive that requires placement in specific biomes. Giving importance to certain areas on the planet and making the player have to create a logistical network to them in order to get their honeycomb.
Same thing should happen for the larva. Currently to mass produce larva, you just need 1 larva alongside nutrients (Royal jelly ingredient may as well not exist). As soon as you get honeycomb production going, the nutrient production feeds everything.
There's an opportunity here for a secondary resource to be used for the larva cultivation recipe. Something else to make the player locate and bring to the production area. Since the planet uses a gleba themed spoilage system, why not have it be a crop that gets grown. I'm actually surprised that a planet themed around apiaries doesn't have any flowers. This could be an opportunity to add in a flower crop for that purpose.
Overall I just felt that Apia was very lacking. My favorite part about factorio is the use of trains, but I couldn't find any justifiable reason to use trains on a planet where everything I produce can be placed everywhere the moment I landed.
