Micro piece of advice... look at this picture of your capital:
Why are you working the lake tile (2/0/2) over the mined plains hill tile (0/4/1)? Surely the 1 extra commerce isn't worth losing out on 2 additional shields/turn while building a settler... right? That's essentially 2 extra turns to build a settler, and those extra turns spent not growing either.
A lake tile is just a very weak option to be working overall. I'd suggest doing something with your floodplains tiles (farming or cottaging) instead!
Why are you working the lake tile (2/0/2) over the mined plains hill tile (0/4/1)? Surely the 1 extra commerce isn't worth losing out on 2 additional shields/turn while building a settler... right? That's essentially 2 extra turns to build a settler, and those extra turns spent not growing either.
A lake tile is just a very weak option to be working overall. I'd suggest doing something with your floodplains tiles (farming or cottaging) instead!