I am interested in this idea (before you ask, I would play a deva), but I may not have the time to actually commit to that interest. Do you mind if I ask a handful of questions before I consider, more seriously, whether I'll be submitting a character?
On the assumption that you'll say "why, no, Chronoclasm, of course I don't mind!" here are the questions that spring to my mind:
1) How structured will this storyline be? Will it be a guided adventure or more of an open-world exploration? As a related question, how free do you encourage the players to be with their interacting with the world around them? (For example, can they write minor, faceless support NPCs--say, if they're in the equivalent of a tavern and want to order food, can they write the waiter or serving maid and assume basic service?--or is it preferred that players defer to the DM, and not write the actions or dialogue of any NPC?)
2) If a character is reincarnated, they retain their skills and names, but do they retain their memories of their past lives as well? If so, are these complete memories, or more of a foggy, far-away, half-remembered series of faded recollections and not-quite-understood emotions?
3) Is a character who dies a violent death immediately reincarnated? Is reincarnation automatic for all devas/rakshasas, or is it unusual? Do these creatures reproduce by "normal" means (sexual reproduction), or are they "born" as fully-grown adults as well, through a vatting process, divine creation process, whatever? Are there family units or dynasties, a "mother" or "father" figure? Or is every member of the society independent and autonomous, with only non-familial alliances, dalliances, and friendships? And could a friendship last across multiple reincarnations, or would that be unusual (see above, re: memories of past lives)?
4) Are you prepared to deal with bow-outs and other forms of player attrition? There's a chance I'll not make it to the end of the first chapter of your plot, and if that should be the case, I wouldn't want to sign up if my leaving would derail the game for everyone.
Finally, 5) are you a deva in real life to put up with all my questions? Actually, I already know the answer to that. If you've bothered to answer them all, you're close enough to an angel to say "yes."