since this was asked and i had a bit of experience with it, i said that its not fun enough.
nobody proved me wrong, so i had to do it myself, as always and...
ac is keyboard playable and fun.

you need the following driving aids/assists:
TC, ABS, Auto-Clutch.
and you need to tweak 3 controls settings for each car:
Steering Speed, Return Rate and FOV(cockpit no wheel cam).
i have yet to find, what "opposite lock speed" does. i assume its the transition speed from left to right steering, like countersteering, but i have no meaningful observation of its effect, if any at all.

some cars might be too odd to be playable. like when TC is not really helping for some reason.
naturally, due the lack of precision, lap times are lacking and mistakes are more common.

right now i have a few videos of how it works.
i just drove a bit with the following:
ks_ford_mustang_2015;
steeringSpeed=0.85;
oppositeLockSpeed=2.5;
returnRate=2.8;
fov=45(1080p, 23", ~40cm away).

maybe ill make a guide one day...

showcase video: https://youtu.be/79Fnn4XS894