I think the reason why writing seems light or that it isn't graded the same might also be the fact that a large majority of people learn how to read and write in school and when they are younger. Whereas, with graphics you don't learn to use photoshop unless you go get the program or go take a course on it. On the surface it may look like media grading is light, but its just that writing almost comes second nature to some now. Even then though, the response you get from a writing grader will help you if they notice something.
I for one would consider myself average at graphics because I'm not familiar with the program as much as others. However the pointers that Frank and Boubabi (as much as I hound him) have given me do help me and I'm able to look at different things. In fact I think it was Boom who gave me tips on text and while back and it assisted me. I don't look at getting a 5 as a shot to my ability, but as a chance to get to a 6 by educating myself through Tuts and PSD's. If losing 1 TPE because I'm trying to progress is a worry, well than maybe I should talk to some guys who get 6's like Jackim and see what they would do. Or better yet share the PSD with them so can give pointers.
The league is fun, there is no doubt that's the goal set out. However if things are given away it just becomes a charity case. A 5/6 is a VHL Fan away from saving your week anyways.