First of all, I see nothing wrong with the so called "homeowner Joe" working his land. To me, that's all part of owning it. It's just when you start dealing with timber sales and such, there are a lot of unforeseen factors that a professional in the field can help overcome. The big one with cherry, as Buzz just stated, is having it split on you as it hits the ground or catches another limb on its way down (especially if it's forked at all). Also, skidders messing up your land can be minimized with the right operator and is still significantly less damage than a large tree coming the wrong way on you and knocking over other nice pole stock and leave trees. Not only does that look ugly, but can wipe out a significant portion of your next crop. And if you think loggers are constantly getting screwed by log buyers, wait until then know your new this industry.
Also, as far as bucking into 8'4'' sections, that is only a small aspect to grading logs. You need to be able to identify defects and know where to make your cuts accordingly. Some mills might not even want 8' logs at the time. It's a very touchy aspect, but like I said before, extremely important. This is where the professional can really earn his keep. We have a certain mill we tend to work with, and we know what specs they want to get the best buck for your logs. Same with veneer brokers and whatnot (who are even more pickier than the mills)
So all in all, there is a lot more to selling timber than cutting and carrying it out to the mill. Good luck, and try not to get discouraged as you go, but try to make it a learning experience.