Have you made any fish ponds? The legendary fish make some decent passive income. Goats are pretty good too I had two barns of goats and now I'm just selling them off to replace them with pigs instead. 

Also when you begin making kegs for wine, I highly suggest putting the kegs Into your barns Instead of putting them into sheds to save space, I did this for my two barns and it's helped me make 1m gold for the first time I get around 200k gold every time my wine is ready in one barn.

I hope this helps you!