Just played Rise and Fall (off) parts 1 and 2. Great races, maybe the best user created content I've played in GTA Online so far.
My favorites were Passing Through, It's Round Here Somewhere, and Paleto Run, with maybe Paleto Run being the best.
I like to explore downtown LS on a motorcycle, and have created one race there, so parts of Passing Through were pleasingly familiar.
I liked how the descriptions were used to create a story.
Checkpoints were well placed overall. Any points that left room for confusion were the exceptions that proved the rule.
The playlists together provide a nice tour of major map locations.
I would suggest placing fewer props on the map. They're not necessary for navigation, due to the excellent placement of checkpoints. Aesthetically, they break the verisimilitude and aren't consistent with the setting created by the combination of locations and race descriptions. I also prefer to turn traffic on when I race, but a lot of these wouldn't work with traffic due to all the props.
While the race courses are great, the default lap counts are kind of grueling. I'd probably knock one lap off of most of the races.
When I realized that Sandy Sores wasn't the last race in the Fall playlist, I started wondering where it would end. Seeing the Altruist camp at the start was a laugh. The traffic was a welcome addition. The unannounced switch to a point to point race for the last entry in the playlist was a little dissonant. Around the time I reached the Vinewood Hills I started wondering how long this lap was going to be, and whether I would need to complete more than one. Great ending though.
Given the theme of social mobility paralleled by geographic mobility, it seems like it could be cool to have a similar playlist that was all point to point races between these locations.
Anyway, great races, the work you put into them really shows.