Planet Coaster 1 certainly wasn’t half-finished. The developers actively listened to the community and constantly made free improvements for years after release.

Sure, it has lots of DLC packs, but none of them are in any way essential.

No cyclists in the base game at launch, unfortunately.

No need to imagine, as they are on Steam:

i7-4790K / 5 1600X with GTX780 / RX 470 and 8GB RAM

Recommended: i7-9700K / 5 5600X with RTX 2080Ti / RX 6800 XT and 16GB RAM

There’s a big difference between European brands though.

French and Italian cars, for example, are generally not that reliable. However, BMW’s (German) are known to be quite reliable. Same goes for Volvo.