Just my 2 influence, but I have two Kheldians that I've put time and effort into, both 50'd and mostly Incarnated up. One has the origin story of being a warrior from back in Cimerora that led a team against one of the Nictus powered invaders and ended up fusing with a Peacebringer when it came to his aid and together they stopped the Nictus. In the resulting explosion of energy so near one of the mystic temples, he was sent forward in time to present day Paragon. The other willingly joined with a PB in modern times as both were part of the PPD Kheld division, but excelled so far ahead of the others that he was granted Hero status. Now, not everyone has imagination for days and it can be a struggle to put something other than "I fight crime because it's what I do" and most don't even seem to bother with origin stories anymore (which is a shame because even the not so great ones are still a joy to read and a dying art). The lore behind Khelds does lend itself to fitting into any origin story since they've been in space, in labs, in the past and around magic. As far as motivation? I got nothing as that really is where the imagination of the individual has to come in. Name and costume? If nothing else use one of those name generating sites and work form that. Some of my coolest creations started from a randomly generated name.