Washington state, like the other flags that rely on their state's seal, has a lot of problems, but at the same time, it has a few features that make it stand out:
First off, it's green. No other state flag can say that (Delaware comes closest with the teal or whatever it uses for a background). The green is even in an appropriate shade of dark evergreen, perfect for representing the Evergreen State. Second, the state is named after George Washington and there he is. Washington state is nothing if not right to the point.
However, this flag contains the problems that most seal flags share; too much detail and text. George looks pretty good up there, sort of like a colorized one dollar bill, but that portrait contains far too much detail for a flag. And of course, the text has got to go.
There are a couple of ways one could go with this flag. The first I tried was turning George into a silhouette, thus removing the problems of detail and keeping the basic color scheme:
I expanded the portrait a bit so you could now see his shoulders and enlarged it as well. One criticism I can foresee is that this removes the different colors, but the outline remains both fairly detailed and vague enough that it could be any of the founding fathers (that wig style was popular at the time). I would disagree with that mostly because you need a little detail to show it is George and not just a random head shadow, but also because the people of Washington are used to seeing him like this. In Spokane, Seattle, and Bellingham, the symbol used on all state roads is an outline of the first president:
I don't think it would be too much of a stretch for Washingtonians to recognize George from the front as they now do in profile.
My other idea for the Washington flag, but one with which I was never truly satisfied, was to use Mount Rainer, the volcano that dominates the skyline of a large part of the state. I lived in Seattle for a while and could see it from my apartment most days and was always slightly surprised when I could still see it when I was in Olympia and points east. I was probably halfway across the state before it would finally sink below the horizon. The state already uses this mountain on license plates and their state quarter, so maybe it could make the transition to the flag:
In the end, I couldn't decide whether it made more sense for the background or Rainer to be green, and I was never very happy with the outline I used (I felt the green and white provided a nice contrast and couldn't find another color that went well with the green). To anyone unfamiliar with the state it could just lead to questions like "Why is there a lump on that flag?" It appears I have again run up against the wall that is MS Paint's (and my own) limitations. I'll probably end up revisiting this one in the future.
On that note, starting in a few weeks, I'll be going back over the 25 or so flags where I have offered improvements and trying to fix the ones that didn't come out right, mostly based on the suggestions I've received. On several occasions, I've been given ideas in the comments where I just have to smack myself and wonder why I didn't think of that. Delaware, Ohio, and Georgia will probably be first, along with the much lamented South Dakota. After a month or so of "fixing the fixes", I'm thinking of trying my hand at either the Australian state flags or the flags of the various British territories. If anyone has any instances where the flags I've offered aren't improvements, especially if I've done the flag of your state/province and have totally missed the mark, let me know and I'll do my best to fix the fixes.