I have resorted to ignoring the line ratings on my graphite rods and fish them with the line that loads the rod to my liking. I fish a 6'6" 2wt Forecast blank with a WF4 and as a 4wt it is absolutely sweet. Most of my rods are built on the Forecast IM6 blanks because IM6 can handle being overlined and costs allot less than higher modulus graphite. Mind you, I mostly fish out of a kayak and rarely make casts longer than 50'. My Forecast 764-4 is my graphite version of a 6wt travel rod and it also sings with the 2 line weights higher.
I also like the Cabelas Fish Eagle Traditional graphite blanks for a really sweet moderate action blank. I've fished the 5wt, 6wt, and 7wt factory rods and they were all really nice smooth casters. I have a 6wt on the bench to wrap as my saltwater schoolie striper/ fluke rod and it will no doubt load nicely with either a 6/7 wt line.
BTW, I am talking about the old version of the cabelas blanks in the gloss grey finish. The new traditional rods are gloss green and I have no idea how they fish.
I highly recommend that anyone looking for a graphite rod with a nice smooth action take a look at any IM6 blank and use a line rated 2 weights heavier as a starting point. You can go up or down from there, but finding a line that makes most rods sing is very feasible if you just ignore the rating on the blank and do a little casting with different lines.
The only downside to this is that graphite is not meant to flex as deeply as glass and I guess the possibility of rod breakage exists. I, however, have not broken any rods while doing this.
HTH,
Lou