As someone else mentioned, the idea of a 'nice country drive' like you had in the USA is NOTHING like what you'll experience driving here. While you can get out to more places from Brides Pool to Shek O, you'll also have to deal with some incredibly narrow roads and occasionally nightmarish traffic control signals (remember: the vast majority of the people who lay out the lines on the road and the signs above are people who ride the bus).
After many years without a car we did end up buying one, but we had two kids who were playing football at different times / locations all over the city and it was just not practical to use taxis for everything (well, we could have, and it would have been cheaper, but sometimes you just can't get a cab and whatnot). It also enabled us to do somethings like take the bikes up to Tai Po and ride around and take the neighbors and kids down to Shek O for a beach party. It also gave us a bit more storage as we kept a few items in the car boot rather than taking up precious space in our house.
Yes parking in HK is a problem unless you have private parking at home and at work !
I'm now spending $500 per week on petrol, 100km per day, 5 days a week, but saving $500 a week on beer in Wanchai on the way home ! Happy wife, Happy life !