I would say that park’s are the most efficient way to build popularity. But art galleries also give creativity, so you could get some nice backgrounds and nft art.
Also if you need population, then buy basic homes. They are by far the cheapest form of population.
The beer event is also good, since you have a chance of getting workers, but also it increases your popularity, so in that 24 hour time frame you will very likely get a homeless or immigrant card.
If you want to build sim income, then look for hotels that are 1050 sim max on the market. Also weed dispensary and restaurant are great as long as you pay around 1000 sim.