Separate names with a comma.
The Letters are A, B, C, D, E, H, I, M, N, O, T, U, V, W, X, Y, Z Then, But since D isn't it, we can rule that out, so i say A
I stick with D
Is it R?
Oh... i called it Wheelie McWheeler xD But what you might could add is a Checkpoint Option for the Practice Mode. (Unless it is already included)
Jump Mode?... You mean something like the Ship in GD? Well the second Flying Section is a bit hard in the beginning, you have to be insanely fast...