Compromise?
Have an Edit Trains menu item as before but it is no more than a "shortcut" that opens the Trainz tab in Surveyor AND ensures the "Limit Contextual Information" is active (for those like me who had no idea the option was even there.) Seeing all those splines just to load a car really ruins any "driver" experience, even if you do have a good imagination. And it would be handy for all the other things like placing a loco, consist, etc. Thus, programmers (coders?) don't have to fiddle with UDS other than putting in the "shortcut."