First off, it is so great to finally be able to build the bases you want in survival without the fear of running out of resource nodes. It really annoyed me that Subnautica 1 never hand any mechanic of renewable building materials/ores.
When i got my first metal farms ready i really started building and realized how fast i can burn through lockers full of titanium, quartz and copper. for the first time i can build the base i want in survial and that is great!
But while i was building, gathering food & water, finishing the story, i periodically harvested the metal farms until i all my storages were full. suddently i having no real reason to go out exploring and that goes against the spirit of the game. suddently it feels more like creative mode.
What bothers me is that the metal farms can harvest any metal anywhere - including all the rare ones like litihum, conduit crystals, enamel, troilite. Also for every material all production times is completely constant. for the rarer metals, wouldn’t it be better if they worked a bit similar like thermal plants? when placed in no special area the rarer elements would take quite long (like now or longer) although some of them could be entierly unavailable for farming in certain biomes. On the other hand, there should be special places (different for each element) where the farms can produce that element much faster.
It would be also cool, if metal farms were not the only source of renewable materials - something like the conduit crystals which are already spawning around the energy towers. need more stuff like that https://subnautica2.nolt.io/7289 . but also the creates could provide some renewable ways amongst other things: https://subnautica2.nolt.io/8257