For an FD, yeah. Especially a single turbo. For a Miata or an NA FC, probably not.

At some point a wing is going to stall. It will still make downforce but the drag will go up exponentially.

 

Shineautoproject's chart showing front and rear CL for different wing angles of attack suggests that front lift due to rear downforce is 11% rather than the 25-30% I suggested, so it is not as large an effect as the simple geometry suggests. But it's not "very very small". And it's far more significant than change in front/rear aero balance from the resulting (small) rake change.

Yup, so you'll need a big splitter and canards/diveplanes/etc.

 

Shineautoproject's chart showing front and rear CL for different wing angles of attack suggests that front lift due to rear downforce is 11% rather than the 25-30% I suggested, so it is not as large an effect as the simple geometry suggests. But it's not "very very small". And it's far more significant than change in front/rear aero balance from the resulting (small) rake change.

That 11% increase in front lift is mainly from aerodynamics- not actual weight transfer across the chassis pivoting off the rear wheels.

You can test this yourself by stacking weight on the trunk lid of your FD while it is on the corner scales or by weighing the car with a near empty gas tank and a full tank as I did.

You say that the lift generated from positive angle of attack of the chassis will affect the front and rear of the chassis and that is correct,

but the increase of rear wing downforce is more than offsetting that lift in the rear and with no increase in front downforce the lift is evident up front.