This turned out really well I think. Here's a test animation of Applejack running that I did in two days. It's a test because I'm gonna use the run cycle for a My Little Pony movie I plan on making soon!
This walk cycle is from Season 2 Episode 25 A Canterlot Wedding Part 1 before Twilight sings B.B.B.F.F.
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It's really good, but I have a bit of advice: the mane shouldn't move much more than the head, its movements should be faster and shorter and it should be paused as the head changes directions, which would make it look like it carries a bit more weight.