To answer the question:
The cartographers (and assistants) who are in charge of the drafting room are there to help you, part of their job is to help new mapmakers to learn the basics of mapmaking.
As for following advice... that's something which you just have to figure out. There are always conflicting opinions, sometimes even between cartographers, and you just have to learn to balance between feedback and your own judgement - it gets easier with time and experience, but even experienced mapmakers have trouble figuring out which feedback to follow, at times.
The point is though, there is no one whose opinion is infallible, no matter how experienced they are. Of course you should put more weight on the feedback of those who have more knowledge and experience, but it still doesn't mean that they are always right, and you should still listen to everyone's feedback and suggestions, even if you don't agree with all of them.