Jujiro,
Yeah, FR and FF seem to be "okay" as is, and both definitely seem to respond well to the new race hard/soft and rally suspensions with little more tuning effort required (all three are nice extensions to the suspension choices imo.. thanks PD!) , but personally, I've chose to view them all as fodder for a full rework, after encountering the MR vehicles, which to me are (not having ever driven a real race car but several dozens of different other "real "cars over the past several decades) all but undriveable as "racing" cars right-out-of-the-box...
Couldn't agree more with "anyway, in gt6, i cannot abuse the car like i used to, i have to respect them. the cars seem to respond to weight transfer more quickly and realistically that i don't really need to flick them to turn, like i used to in gt5 where i triple-flicked (or double feint-flick if you will) before slow hairpins but if i do the same on newer version i'd just spin out of control...", at least before I tune them. Most of mine are behaving very well now, but it definitely cost me many laps during the tuning procedure.
The new suspension is a thing to behold. I'm still enjoying playbacks watching my car begin to fail on a curve entrance or mid-turn or at the end, watching it unglue as the car rolls over that invisible line between control and chaos, and how I can actually see why it's happening. Fascinating. Or watching how the suspension moves when you hit the rumble strips, how it feels when you're driving, etc. Very enjoyable. Not because my car spins out or rams the wall, but what I learn in those few instants, and which leads me to my next suspension/aero/lsd tweak to stabilize the machine for the next set of laps.
In any case, I'm tuning everything that I drive for more than a couple laps, no matter the drivetrain type. Every one I do helps me to understand the process better.