Nearly got a Skyline to level 30 just doing Rivals time trials all night. Definitely more of a slog than it should be to get those car points.
Gonna try setting it up for A/S class as @Adamm. suggested.
Yeah it's a lot of fun just building and tuning and trying to improve lap times. A/S usually seems about the sweet spot imo but as we saw the other night plenty of fun can be had stock cars too.