Biggest problem I've got with creators club is the frequency, I downloaded the Orient Red livery for the DB143 but found it was appearing on every other 143 in the game which broke the immersion, so I deleted it and I haven't bothered with CC since. If only there was a way to set a spawn rate of content and even route specific, for example I want the Orient Red 143 to appear 5% of the time on Dresden Riesa, 10% on Dresden Chemnitz but never on any other German Route. A simple drop down of all relevant DLC it could appear on each with their own slider, with a master slider for those who dont want to tweak individual routes.
In fairness that's the same as livery designer. When I first made a livery for the BML 377 all of the trains in Victoria bar about three (excluding 387s and SE stock) were in this livery. It'll probably be consigned to the seemingly mythical Livery Designer 2.0.
I personally would like to be able to adjust the departure time of services in the scenario planner, to allow the set up of other services in the scenario.
I'd downloaded the poppy livery for the class 395. In reality the livery is on one train yet there are many 395s running with poppy liveries which killed immersion. I agree that there needs to be some sort of slider to set how many times an ai train will run with a livery downloaded from creators club. Hopefully once more improvements come to creators club, this niggle can be resolved with the improvements