Support! I could lean towards any of these, honestly, as long as there's a main color with splotches of two accent colors. <3 And harlequin would make for some very fun dragon designs, especially if it were to become a universal gene for both moderns and ancients!
That said, my own preference would be to potentially have a white base color with splotches of the prim/sec + an accent color. I know it'd likely come out very similar to piebald/paint, but I think if the splotches were focused more along the dorsal side/wings it could make for some interesting patterns (particularly if the accent is the more vibrant accent for given colors, like radioactive's cyan accent and pearl's baby blue accent that only seems to appear in pearl poi/tox).
That said, my own preference would be to potentially have a white base color with splotches of the prim/sec + an accent color. I know it'd likely come out very similar to piebald/paint, but I think if the splotches were focused more along the dorsal side/wings it could make for some interesting patterns (particularly if the accent is the more vibrant accent for given colors, like radioactive's cyan accent and pearl's baby blue accent that only seems to appear in pearl poi/tox).