The only “legitimate” concern I recall being voiced is the advantage that Dracthyr would have over other classes in completing old content.
But with the introduction of Dragonriding into old content, this becomes a mute point.
Stay tuned for Soar to have zero cooldown, and Dracthyr being able to utilize all of their dragonriding upgrades without needing a dragonriding mount. It’s definitely happening… soon-ish.