This anchor is where I have some agreement with the concept that prototype modeling creates better modelers. If you want to improve your modeling I think the best way to do it is the attempt to model a piece of prototype equipment as best you can. No mater what skill level you are at with your modeling the attempt to do your best to create a prototype model of some equipment that you have a lot of information on will help you improve your skills.
While things have improved somewhat you need to have some caution in this area when you buy factory painted equipment lettered for your prototype railroad because from time to time what they do at the factory is not correct.
While I am not modeling a prototype railroad this is an anchor area for my layout. I plan to carefully model my equipment using information from the builders that supplied the equipment that ran on narrow gauge railroads that had cargo and traffic levels that would compare to my layout. Carefully modeling the equipment also includes having the correct details on the cars and locomotives (for example the correct brake systems, lights etc..)