Hmmm, these days I was thinking about the same thing. I mean engine tuning, but aero too for "srteet" cars.
That can be very interesting because with similar cars but different mods you can try many others things, you don't use the same braking point and the same line ...
About drifting, this is great as it's now, but with aero tuning & engine tuning (for getting something like 50 / 100 hp more, not 600 hp cars) that can be very fun as it's in real life.
You see, something like the tweak but as an optionnal way in the server config; and some servers can try to go a "Gran Turismo" style for performance improvment, as it's done with cars in cruise mod for several servers.
For all these things, I keep in mind "realism" as I use LFS as a simulator for understand et learn more about chassis tuning & driving techniques (and wow, that helped me a lot !!!), and drifting is very realistic in LFS (not like arcade games), the only problem is about the tires ^^ but I guess that has been planed to be fixed.