The correct number of Skyways in Cool Ranch is 6: Santa Pollo, Big Sky, Cooper's Roost, Arroyo Grande, Tumbleweed, and Haunted Skyway. I agree that Arroyo Grande is small but it is still called a Skyway.
Doing all the quests, you get to Cool Ranch about level 18 and finish the second part about level 45. If you leave before level 40, it is my impression you will have trouble soloing in MooShu.
I would guess that if it were shorter there would be more complaints that MooShu is too hard.
There is (mercifully) a short break from All Things Chicken where you do Port Regal. Cool Ranch is big (and seems interminable) but at least KI had mercy on us and gave us the stagecoach. Pity the poor pirates who had to slog through it sailing from one end of a huge skyway to the other just to reach the skyway on the other side and sail through that because some sadist at KI thought it'd be funny to make you go from Santa Pollo all the way to Tumbleweed.
And yes, the jump up in difficulty from CR2 to MooShu is incredible. You need to get as high up level as you can before you go there.