Funny, contrary to what I prefer for trout fishing, I use nothing but fast 9'0" graphite for all of my fly rod bass fishing. It's what I prefer because for me, it does what I need it to do regardless of the flies I am fishing, I like the length when I'm wading and the light weight at that length.
My quiver consists of a 9' 8wt Orvis Power Matrix, a 9' 7wt Winston LTX and a 9' 6wt Winston BIImx, all bought after they were discontinued for deep discounts.
When fishing, I just tweak my leader length and tippet size depending on the fly size and open up my loops by changing the casting arc when necessary and all is well.
What I have discovered over the years are some "specialty" lines really need to be tried, before they are "buy-ed" because many rods might like the next size lighter or something completely different for different sized flies. Case in point; I HATE the Rio Closer line for anything!! However, I LOVE a 333 Bass Bug line I have that is at least 30 years old but in like new condition because I baby it.
For that reason when I bought my 9' 6wt BIImx, I put in many hours of research, picking the brains and explaining my application and casting style to Rio and Sci-Anglers. I chose the Rio Smallmouth line and couldn't be happier!!
Obviously YMMV.