It's so great to see ranked multiplayer doing so well and I've been having countless fantastic clean races. With the handling now at a top tier level thanks to the physics update, I wouldn't be surprised to see many IRacers start migrating to raceroom, because with it's superior(imo) tyre model and vastly better price-point there's very little to keep an informed simracer at Iracing anymore. However the one thing missing is splits. This might sound trivial but when I was at IRacing, there was a of sense of accomplishment when racing in a popular series of climbing the splits and eventually getting to the point of competing with the top split of a 5-6 split series. (Well honestly I never got there, but that was the dream! lol) The first come first serve method current being used by RRE is totally serviceable, but I think to truly make it 'the only place to race multiplayer seriously', splits will need to come into it at some point. I understand this would be a huge amount of work and a complete rewrite of multiplayer code but hope this is something on the minds of the devs.
Read the May dev notes. Edit: I actually went there and there nothing about splits. But, yeah, they're coming. You'll be able to sign up for a race and be placed with similarily ranked drivers