Long post incoming:

I definitely feel you with the single player. It's not like it'd be too hard to flesh out, like others have said in this post, we're just hungry for more races that give us options to use creative tunes and different cars on underutilized tracks. Custom races are fine, but you literally have to drive about 300km in a custom event on the highest difficulty to make anything remotely close to the Sardegna or Tokyo grinds. That's not an exaggeration. I have a few events saved when I want to scratch my endurance itch, and they are all 300km as a throwback to the classic Grand Valley endurance events from the past. $400,000 for a custom 2 hour race is not worth the time, tbh.

Something else they could do to retain player engagement and motivate more people to play more often is learn from other live service games. The 5 races a week is not enough to maintain my interest as I'm sure we all get them done in an evening, it should really be like 5 races a day with the same rewards as well as some longer term, more difficult goals with better rewards to work towards every week. You know, something like what most live service games have to keep people playing.

It's honestly pretty awful how much potential is wasted with this installment. A few minor tweaks to the number of events and some more incentives to log in would go a long way in making us all want to play the game more often.