One thing in the modern day railway that will always frequently run wherever you are on the railway network is the Colas operated test trains. This fleet of class 37s, 43s, 73s, 153s and Mk2 DBSOs along with their Mk1, 2 and 3s operate a range of test trains from Ultrasonic to Plain Line Pattern Recognition and the famous New Measurement Train, also known as ‘Flying Banana’. I think it would be quite nice to have these service incorporated into the game as an addon that will cover most modern day mainline routes, with a variety of services using the different stock, I would also like to see the DBSO not just work with a 37, but the majority of other locomotives in the game to allow for free roam versatility. I have some images (not of my own) attached for reference to these test trains:
Could also add in a Colas Thunderbird pack. Colas have two 67s on Thunderbird duty ATM and also had a 70 when one 67 wasn't ready. Could be interesting if faults were simulated properly, would be fun to run on the ECML at a random time of day to haul a striken 91 (it's basically always a 91) and see the timetable play havoc. Does rely on DTG implementing it well though.
