I could see us being given a single customizable mount.
The various customizable dragonriding mounts in DF were clearly to smooth over the fact that you didn't actually get many useable mounts from what was then probably designed to just be a one-off expansion specific system.
Without it everyone would be using the same mount essentially.
Now that dragonriding will be the norm the focus is likely to be on making all flying mounts able to use that system so we can have the massive variety of mounts, rather than fifty different shades of Dragon.