If you have a budget and can afford to buy 3 mods, buy one and save the rest of the cash for maintenance and incidentals.
Like you said, stiffer isn't always better, for a dd I have to keep comfort as a priority.
It's been good reading on how to maintain the car, saves money. But it really helps to have a friend that knows more about cars than you at least the first few times you're trying something new.
Make friends with your local dealership, if not the service attendant then the parts counter. This has come in handy for me because the nearest specialty Subaru shop is 7x further than my nearest dealer.
Keep records of your car.
Ignore the creaks, a big one for Subarus!