In recent years, so-called 'tycoon' games have become something of a byword for mediocrity, with the genre extrapolated to cover the most unlikely of subject matters. Other times you might want to add a new ride here, a new thing there and expand at a slower pace. Sometimes, you have to just stick with what you have for a while to make some money before you can do a big expansion. I would change my prices regularly as well as work on keeping my park fresh. Keeping your park guests happy and spending money is really addictive. Some people may complain about your prices, but the profit margin on stuff like this can be huge and as long as they are having enough fun, you can get away with it. You can do this in many different ways, but for me, the best way is by making stuff like your food and drinks as expensive as they can be. One way that is fun to make some serious money in RollerCoaster Tycoon 2 is by fleecing your park patrons for everything they have.
You may lack the budget to do this so you have to be very smart with the way you go about expanding your park.
While you may want to expand your park at a rate that is just insane. You see a huge part of the game is keeping your budget in check.