There has been some debate about the possibility of a Modern Day/Late Start DLC. The devs didn't comment on it, but there seems they're planning to work on a modern day game around the same engine and idea than WRSR.
First of all, I do think that such a DLC would be the perfect opportunity for them to study and test many features for a new game with direct feedback prior to investing into a brand new game. I don't think that the new game would have its market affected by this one, as they would be different in setting and in mechanics (likely there will be no loyalty, secret police, etc). But it would be very nice if this were a ground test for the new one and thus both games would be improved, plus they would have compatible assets which would make work easier.

Secondly, there are many assets we miss in this game that would match a modern day game and that would improve this one, such as:
-semi automated factories (require less workers);
-advanced maintenance systems (info from maintenance and decay could then be divided into manual and automated);
-electric or hybrid (llower fuel consumption) vehicles;
-high speed trains (workers could reach the other side of the country if needed);
-ride apps (like uber, instead of owning a vehicle we could have a system in which workers could ask for a vehicle that whould deliver them to a place and then go to do so to another citizens instead of being parked there);
-e-waste;
-a new electronic which would be mobile phones;
-the need for internet access and to make buildings smart (thus increasing loyalty but also working as secret police);
-organic and vertical farming;
-bigger fields with GPS machinery;
-smart grids to ballance power and reduce outage;
-dual-piping water system filtration;
-revamped parking lots;
-priority lanes for either transport trucks or passanger vehicles thus reducing traffic;
-improved, larger containers;
-improved DO's to simmulate Just in Time (small stockpiles) with the option for some vehicles to not load to the point that you leave it empty (thus one depot can be used both to exports as to internal supplies);
-techs that you can buy only from one of the sides of the Iron Curtain (yes, techs, you should be able to buy Western techs thus western models for factories);
-dynamic events on both sides of the Iron Curtain (such as shortages on the East and embargo from the West) just so trade becomes dynamic;
-no inflation and some subsides from the East and the risk of embargo from the West;
-modular factory production, just so you can produce or buy specific prefabs to make construction of specific buildings faster;
-intermodal airports, which combines airport, train station, and truck loading station;
-improved fuel farms for huge storage;
-a ready model for cloverleaf roundabouts;
-high speed roads for delivery trucks;
-semi automated shops, airports, naval docks;
-cctv and facial recognition/social credit systems for citizens (serve as monuments, slightly increases loyalty beyond cap and reduces will to perpretate a crime);
-better policing due to automation - more cases per district;
-digital tracking of citizens in quarentine during pandemic (reduces chances of getting sick);
-medical tourism (specialized hospitals that works as attraction);
-emergency care units (small specialized clinics with fewer doctors that can provide care for more citizens).

These are some I can think of. Please share your ideas about this topic, comrades.