Enhancing certain areas could be interesting. There are places that characters have to avoid until higher levels as is.
"Valinor" sounds like an interesting challenge, albeit one out of my league
. Remember parties of more faint-of-heart players might be turned off if you can't complete Koran's quest. Especially if they want to grab Koran as early as possible and then power level him up to face challenges. Maybe if you put him in the little cave near the druids, where the two baby wyverns and the weird "ranger" guy is.
Sounds interesting so far.