I agree @bruceleroy98 that it is super easy to make money; maybe the economy progression could look like in addition to bills/rent paid each week.
1) There could be a monthly tax day where a percentage of the income is paid towards taxes (unless sims volunteer or donate money away to bring it down).
2) A way for sims to take on more debt. I like the system they implemented in Discover University to take out student loans if a sim couldn't pay for college. Sims can take out loans if they want to buy more furniture, a bigger house, etc. This would reduce the temptation to use cheats for more money.
3) Like @atreya33 said, The Sims 2 made simmers pay for clothes/groceries, it wasn't free. I wish we could go back to that. High Schools Years EP introduced a way to pay for certain articles of clothing but like it was only at that one boba shop, etc. I want the option to either online shop or go to a physical store for groceries and clothing. I also wouldn't allowing sims more services to pay for like a matchmaker, making the childcare cost money (when give an option, my sims always choose the free daycare over the nanny), and go back to having a newspaper/magazine service that comes to the door cost money.
4) A separate banking system for sims that are teenaged or up. So like teen sims who work a part-time job have their own bucket of money that they can pull from and if they don't have enough on their own to go to university or whatever, they can ask their parents for some of the "family money".
