Hi Chris,
I have probably spent more effort and life on this than I should have done. I'll offer this in the hopes that you will save some of your time...
All of these comments were true for either pizz or arco, for me.
I would expect your sound to change, but you might not like it better. My modest, limited experience with carbon fiber, wood, or other lightweight pins, tinkering on three basses, is that they seem tend to make the sound brighter and more transparent, with a bit more projection of the upper and upper mid ranges, but that they seem to often cause the volume and "darkness" on the bottom strings, especially the E, to fall off a bit. Even if you just cut off the steel rod to the length you need, you may lose some of the bottom end.
What size pin are you using now? I would try (and have done) experiments with replacing the rod itself, first. If you have one of the common sized pins, you can buy a carbon fiber rod (or ready-made pin) for minimal cash. Here's a link to a retail CF supplier:
http://www.graphitestore.com/items_l...d=34&curPage=3
As far as tinkering with rod length of the steel pin, the local hardware store may have rod you can mess with; hacking off different lengths of 3/8" dia (or whatever) steel rod to approximate endpins of various lengths. (This will save you from cutting your good pin and then wishing you hadn't.)
This is a wacky thing. Not just mass, but actual material characteristics affect sound subtly. I am currently going between two endpins that weigh exactly the same (within .1 gram), but one is carbon steel and one is stainless. Even with the weight being the same, the sound is different.
Here's a link to surefire endpin madness. While this guy is mostly for celli, it gives some idea of the bottomless pit one can fall into:
http://www.frenchcellobow.com/products/endpin.html
Note that he says that Gary Karr is currently using a composite pin made of brass and carbide rod. I priced these; a guy in Japan will happily custom make you one, in any diameter, out of any materials, for roughly $300.
I am currently using a New Harmony endpin socket (lightweight Delrin) with a 1/2" carbon steel rod. I am flirting with a stainless steel rod, too. When I used the CF rod that came as a standard with the New Harmony pin, my bottom end completely fell out; my E string lost all of its "push" and "bottom".
All the pins I have tried in the past six months:
nickel silver solid rod
solid oak dowel
carbon fiber solid rod
hollow steel tube
homebrewed composite, with carbon fiber core inside of a hollow steel rod
Here's a place to send your money if you want to tinker with different metals (they charge a restocking fee, if you return them, BTW):
http://www.onlinemetals.com/
All of the above lighter-weight options had nice, varying brightness, clarity, and projection, but all lost the bottom end volume and fullness on the E string, to varying degrees.
I have seen the same thing happen with a carved New Standard La Scala, fitted with a New Harmony CF/Delrin setup; the E string was weak, where this is not at all typical for those basses, as you know.
So, to summarize, based on my limited, modest experience; one might do well to move slowly with various trial materials, before one commits to a final replacement or into cutting an existing steel pin.
I just wonder if a shorter pin that doesn't have all the weight and stuff sticking up inside the bass would make much of a difference. What I need, I think, is a little nub of a pin that will still hold onto a tip and a crutch tip for practicality's sake.
