first of all, the truck station and the vehicles for them are largely useless, they are only useful for a very very limited time, because with only 1 input and 1 output slot the truck station cannot outperform the conveyor belt hooked into it, a diligent engineer will likely be producing loads of iron plates or reinforced iron plates to simply belt the resources over long distances before its even available.
2nd, the storage containers... only 1 input and 1 output slot?.... come on, atleast 4 of each please, if not for the basic one then atleast from mk2 and up
3rd related to 2nd, alternatively to adding more input and output slots, make splitters and mergers attachable to slots.
4th, the slugs... instead of merely producting more of the same from the different color slugs it would be better if yellow worked like this: 100% overclock and same power consumption as green, purple: 150% overclock and same power consumption as green, and make it so red takes up all 3 slots and yellow 2 slots, that would motivate us more to go slug hunting.
5th, power generation: wind mills, water mills, solar panels, or even a large hamster wheel wtih a dynamo for the doggo to generate power, and capacitor banks to store and act as buffer.. reasonable request?
6th, military hardware(something that goes boom), and also more equipment slots on the character one of which is a belt slot for toolbelt so you can quickly swap between atleast 2 handheld items with the press of a button, as it is it feels silly like "oh no, im in a gas area and im wearing my fancy blade runners... best i take them off my legs so i can put the gasmask over my face"
7th, the space elevator, a majestic monument for sure.... but useless.... you send away some stuff a few times then it just stands there doing nothing at all... how about letting us trade resource with the man above? load up excess resources and sell for credits or trade directly for another resource.
8th, a map... you send stuff into space... someone up there is bound to be taking selfies with the planet in the background, get us some images for crying out loud!