Suggested

Driver, or all people

I saw that many drivers and management peoples have all 20 abilities points... 20 talents and all others at maximum....

What avout use 30, 40... Or 50 points system??? There can be more difficulties betwen drivers and all others.... 

I was thinking of something similar.

Once someone reaches level 20 and their drivers, HQ etc are all at 20, that's it, that's as far as you can go. So I was thinking that regardless of where your drivers etc were, you unlock a 2nd tier of the game. It could have all kinds of things, more set up options, different sponsorship challenges, where as the team owner, you have to "sell" the marketing opportunities to the brands (I haven't really thought that one through, yet)
Then, maybe when you reach level 30 or 40 you could unlock a 3rd tier which might have extra tracks, new livery designs and so on.
Yes, I'm well aware that this idea would require a lot of work but at least it gives people somewhere to go after they reach level 20 because at the moment, you reach level 20 relatively quickly and then.... Nothing.