I was trying to do some research on the subject before getting FM4 Essentials, but the results were ambiguous. So now I know.
I am at 97,8% with no more available races to finish. Apart from certain time-period car packs necessary for completing some races I am missing two specific cars - Lamborghini Gallardo (for Gallardo Club event) and Shelby GT500 '07 or'10 (for Shelby Showcase event).
The "funny" thing is I could probably get them while progressing during the first 50 levels, at least they appear on the lists of car prizes, but how could one know when in World Tour mode? So after 148 hours I am done with the game, without the Bucket List achievement obtained. Saying that I am frustrated is not really necessary.
The thing I don't get either is the green (or blue) icon on some events, suggesting I am in possession of necessary cars, but any attempt to enter them results in visiting the shop with DLC, cars, which are obviously unavailable.
Still can't understand how such a flawed product could be released.