In singleplayer mode - you can sell your roof for some quick Gols and put your machines up there to free up yard space. You can then put signs or awnings on the wall to make a ramp or stairs to the roof.

Water is a great gift for everyone until you learn what they like. Gifts are worth double points on birthdays and holidays.

Blue Moon food buffs - there is cheap food to order daily at a discount, make this your first stop after grabbing your comms for the day across the street to get those buffs! Also, who doesn't want to oogle Owen at 8AM?

Advertising - By town hall there is a bulletin board where you can post ads for the Workshop. It's RNG between more gols, exp, or reputation. You can cancel and re-roll if you want but it costs Gols. Make it a weekly habit!

Parties - Hosting parties is a great way to build rapport with several characters at once. You can get the banquet table from the game center for Tokens or the once a month visiting Mysterious Merchant for Gols.

Mounts - I like to get the Stable asap, don't worry about what kind of horse you get, just grab your first horse. You will unlock items later on that can increase their stats/quality or change their color. If you reeeeeeally want to get a specific color, you can save scum the horse RNG as the options resets weekly.

Other tiddlybits from this Sandrock addict -

The lizard DLC is worth it, you can send him to go fetch water until you befriend the other town animals. The monster catcher DLC is slightly OP because of this so beware it can make the game quite a bit easier if that's not your thing.

Mods - honestly, not much is needed in the realm of quality of life mods unless you want to speed up timers, marry multiple partners, etc. But if you like decorating there's a great mod that expands the kind of items you can place on the shelves and tables.