Well, my initial thought is "If it ain't broke, don't fix it." But, I know I would probably do the same thing.
What (if anything) would you like in a crankset that your current crankset doesn't provide?
I just installed a new M361 crank on my Trek 7.3 FX, since it pretty much matches what it already had, but I switched crank length. The M361 could be suitable for your bike, and is available very inexpensively. If higher end is your thing, go as high in the Shimano line as you can, while retaining 8 speed compatability.
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Slow Ride Cyclists of NEPA
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