Any tips on how to get the most money in the 1st year / season?
I don't have an excel sheet to back it up but:
Keep investing in your farm's production.
Like, don't bother getting a coop, or a barn.
a coop costs 4000g. 4 chickens cost 3200g. An egg sells for 50g (depending on size and quality).
So for 7200g you'll get revenue of 200g a day.
That doesn't mean you should overstretch yourself with regards to farming either, as you'll need to grow your farm in accordance with your technical capabilities.
You don't want to be dropping to 1/3 energy each single day from watering your plants, that'll severely impede your progress in other areas of the game.
Like, stick with the "invest money in backpacks upgrades and seeds, grow your farm - use the time off to mine for ores, which you'll use to upgrade your tools to make you a more efficient farmer" loop at first.
Stuff like building a relationship can be done once your income's at a comfortable level. As soon as you can "mass produce" gems (like Diamonds, a universal like) and you optimize your gift making around making gifts on people's birthday, giving them items they love - you'll make much faster progress with the villagers than handing them daffodils in Spring 1.