I wonder if the high-speed positioning will mean players mark their starting spot before closing in and hopping back. Perhaps it will be similar to Ley Lines, a mark that persists for a length of time before it naturally disappears and you have to lay down a fresh one.
I wouldn't like just to jump back randomly to where my character's back is directed to. As a DRG I hate that elusive jump sometimes sends me off platforms ;x

I also don't see RDM getting access to healing white magic from the get go. I can see heals being the last stage of any combos, probably be a mild AoE before jumping away again. Although even an AoE heal I would rather trade for an AoE regen, so it can time in with any rotations. Would be nice if we can set the magicked crystal like a turret and have it spam mild AoE heals while we melee but its a caster not support.

However I think the main focus will be buff type whm spells like bravery and faith or even oil even though that is green magic (to increase damage output due to having abilities not as potent as blm or whm) and debuff type blm spells like syphon (to ensure all RDM take a break from chain nuking and go and melee otherwise they cant recover their mp)