I use my noodle rod at times as well. I think 9'. I have a sturdier salmon rod as well, that I use for trolling for larger fish as well. I find them both to be rather hard to use from the boat, casting wise with things to get hung up on, including a fishing partner or two. It is nice if trolling, to have it out further than my 7'. The 7' is much easier to use for casting from the boat. Same reason that I rarely fly fish from my boat, too many things to get hung up on. The longer rod is also nice for the rare occasions that I vertical jig into a weed bed or brush pile, a 15' cane pole would be much better, but don't do this often enough to ever purchase. I also wade a bit, and the noodle is nice for getting the light offerings out further, but weighted bobbers do about the same with the 7'. To me, unless you plan on using it for trolling or always fishing alone from your boat and want a bit longer casting distance (what the trolling motor is for...). From shore, the only time I can see it being an advantage, is if fish are holding out rather far, and you need that extra 10' cast. But, it better be pretty clear on your back cast, with trees/brush, ect.
Another advantage, which I never do for crappie, is if you wanted to free line fat heads or small shiners. Or, if you have some small jigs/lures that you didn't want to use a bobber or casting bubble on a shorter rod.