Build requirements:
Action Boost: Movement Speed, with the most uses possible
1 level of Barbarian for the 10% base speed bonus ( at least )
Spring Attack Feat - I realize this will probably not come online until near the end of heroics.
I am torn between Human for Dimension Door and Dragonborn for Memory of Flight at early levels. Personally I feel like Memory of Flight is overall more useful than DD, and if pugging, there's a chance someone else will have DD that will help you, while someone else having Memory of Flight will not, so I prioritize getting Memory of Flight first, and begrudgingly accept that means no Dimension door until epic levels. (I know that past life racial enhancement points will make a huge difference here in terms of how early Memory of Flight could be attained.)
Any other "Leap" abilities that operate on different cooldowns, or perhaps adding Leap of Faith from Exhalted Angel even if it does share a cooldown, since it can store up charges that can be used fairly quickly when needed.
Optimization:
I'd like to see a heroic class level split something like 9/1/10 or 6/6/8 where the 10 or the 8 would be cycled through all the classes for reincarnation, and the other classes would remain fixed every life. I know this screams inquisitor crossbow build, but since that's been done to death, I'd love to see a different take on this. Or, alternately, could a Feydark caster build work? Color Spray/Fan of Shadowblades/ Shadowblade + some level limited AOEs from 9 levels of another caster class potentially? I feel like if there's a good answer this is where it is, but maybe the damage output would be too restricted to be useful
The goal here is to gain these speed/leap abilities at the lowest levels possible, to allow bursts of speed, especially in those quests where you have significant space between areas where you must fight things (Think about Red Rain from Masterminds of Sharn). All this without hurting the survivability and damage output of the build. No point in being able to move more quickly, if your damage output is so low that it restricts how quickly you can move through a quest.