Oh well, if it takes some (or allot) more time I don't mind. My favourite is dry morning racing anyway
I know, but there is a workaround if you will. Try changing the AI slider 5 or more points and the weather will change, at least I found that being the case for several races.
This is pure speculation on my part but we could get some form of night racing thanks to the partnership with the WTCC. For those that don't follow the WTCC, last year saw the series visit the Losail Circuit in Qatar for the first time as it hosted the first night race in WTCC history. Not a real night race as such, but one held under floodlights like the F1 races at Bahrain, Abu Dhabi and Singapore. Moto GP fans will be well aware of the Losail Circuit. As I said, pure speculation, but Sector3 seems to be focused on bringing the missing WTCC circuits to R3E and maybe Losail will be one of those? At least it may offer the possibility of a floodlit night race under static conditions. Personally I really like these night races held under floodlights. Much like football matches under the lights, it's more atmospheric and everything looks better.
I am fine with how the time of day settings are right now. Lets be honest here. Just how much racing goes on at night. There are what 4 or 5 big races? and with the race series modeled in RRE, how many of their races happen at night? Id much prefer more content (tracks/cars) being added then to see them devote time and resources to a "project cars like" day night scheme.
I tried to but their AI mostly ignores the fact that you exist and is so inconsistent in pace race-to-race and car-to-car that adjusting the % slider every single event got old fast. But mostly I was referring to multiplayer sessions, both public and league/club, where nearly all the events happen in clear or slightly cloudy conditions around 1:00 - 3:00 PM time of day settings.
I don't think we see any changes to that for a while, a lot of work needed to rewrite the engine to support it, you may see if there ever is a change to UE4, but that may also never happen so who knows.
AFAIK you can expect a change on that topic, but I wouldn't say it is foreseeable at the moment. As @AlexBlob already wrote, it would only happen when a change to UE4 will happen. I remember an Interview with Diego Sartori (Creative Director from SimBin back in the Days when Raceroom enters public Beta). In that he told, that the Graphics-Engine of Raceroom does not contain Weather-Simulation and is not capable for Dynamic Day/Night-Transition nor Night-Racing as it can handle only one Light-Source.