I'm approaching 50, if I could go back in time and talk to my 29yr old self (which I was in the same financial situation as you), I would tell me to set practical aside for later and go for the fun stuff now!
Typically, nostalgic memories are the fun times you had and things you did (regardless of the consequences). Whereas regrets are the "safe bets" and practicalities that kept you from doing the more enjoyable things.
Do the fun thing now, when the family situation comes around...Well hell, the Stinger is still a 4-door hatchback man! And if you opt for the AWD, it'll be great for bad weather too! It's win-win here.