There needs to be some adjustment in favor of Train Station. They are mutually exclusive, but with addition of 250HP to Seaport, it's a no-brainer which one to choose.
Seaport: -6; +25%; +1 from ocean/coast, +2 from sea resources; +10% supply cap; 1GE slot; +250 HP;
Train Station: -5; +25%; +10% ; 2GE slots;
I would give TS +10% growth or some other representation how it made people move from villages to cities. And some increase in supply cap as well, after all it somehow made conscription easier.
Seaport: -6; +25%; +1 from ocean/coast, +2 from sea resources; +10% supply cap; 1GE slot; +250 HP;
Train Station: -5; +25%; +10% ; 2GE slots;
I would give TS +10% growth or some other representation how it made people move from villages to cities. And some increase in supply cap as well, after all it somehow made conscription easier.