Hide stacks of 200.
Loom inventory of 60.
Imbalanced ship parts loot between maps/whales/Kraken/Yeti. Uber drops from maps - e.g. ship cannons over 300% damage, medium gun ports over 250% durability and utter trash from the rest - low grade blue/green from Kraken 2 e.g.
Player shop limit to 100 000 gold in offers, but 75 slots only. If you sell something priced 100K, you will lose 25K upon sale.
Treasure maps locations.
Inadequate weather system - Storm, Fog and Cold front at same time. Heat waves in Polar, Cold fronts in Equatorial.
That list can go on and on...