Question on "Custom Event" and "Custom Championship" PS4

[likewise 19]

(PS4 dreaded console gamer) I don't understand why you can't pick your location's/Stages in a "Custom Championship", You can in an "Custom Event" but you gain no credits or experience points (didn't check if it counts towards distance traveled for the engineer perks)! The stages are pretty hard to master and require a ton of practice, but the Custom Championship just drops you into a random event and you can't repeat it... Am I missing something? 

Also my "saved tuning settings" seem to change randomly for each race...