So now that the style is sufficiently defined, it's time to get to the substance.
Though I like using D&D rules systems for several reasons, I don't want this to be a D&D world that has everything from the PHB and takes most other stuff from splatbooks. In recent years, both Dragon Age and Mass Effect have been great examples for settings that are original and have both cultures and creatures that are different from the generic kitchen sink stuff.
I did have a couple of ideas, but those really didn't work out to become something great, like lizardfolk being the most numerous race with the largest empires.
So while I am working on this, you are invited to throw in suggestions yourself.

What I have so far:
- Wild/Wood elves as the "primary race". They have a couple of major strongholds the size of small cities, but mostly it's small villages that do some farming for fruits and vegetables, but live mostly on hunting and keeping sheeps and goats.
- Wild Dark Elves, as in the Eberron setting. They are basically drow that live like wild elves, but are mostly nocturnal and spend most of the day in cave homes and come out only after the sun disappears behind the trees of the jungle during the afternoon and village squares and markets begin to really fill around sunset. They are also influences by Dunmer from The Elder Scrolls, which I like quite a lot.
- Gnomes as the only short guy race, as they can be both like dwarven miners and smiths and halfling thieves at the same time. Calling them gnomes also helps to reinforce the notion that these guys are not the generic rude alchoholic scottish viking miners. Whatever you do with dwarves, they always turn out that way and I don't like that culture. And with having gnomes, halflings become redundant.
- Humans have to be in the setting becuase otherwise everyone will think this is an elven fanboy setting and nobody would play it. The difference is, that humans are one of the minor races who are not particularly numerous and lack big cities and great armies. They are what the Greek and Romans would have called barbarians, simply for the fact that they are not part of their culture and not as advanced as they are. There are enough of them to run entire campaigns limited only to the small human lands and they can also be played to start with something familiar and the set out into the wider world, where both characters and players learn more about the rest of the world.
- I still want to keep lizardfolk, but I think I keep them down to be savages and either live in small camps in the southern jungles, or as the legions of servants and soldiers for naga, who are and ancient and highly advanced race from the spiritworld.

If it needs to, this would be enough races for a setting, but I think it's also an opportunity to ad some really new and original things to it.