Tinkering with Eberron...

[Ketjak]

Gladiators are easy

Gladiators and their venues

Aundair: tournaments are the center of festivals celebrating every possible event. Rural townsfolk gather for these festivals once a year, while cities host them once a month.
Breland (Sharn): there are already towers in Sharn that offer everything... and, of course, there's the undercity. Anything goes there.
Karnath: bloodsports must be common there. Imagine a dark circle with a sandy floor smelling vaguely of iron and sweat. Muscular captives fight for their lives... only to realize living means fighting again the next night, while losing means feeding a vampire lord with the last of your blood.
Thrane: the ultimate evil must be fought by an ultimate champion. Armored knights fight each other nearly to death for the privilege of being one of the Flame's Sacred Blades. Losers live with having failed...
Mournland: the Lord of Blades (or another foul beasty) captures weak flesh for testing against his followers. Not only does it focus their cause, it desensitizes any warforged still concerned about killing the frail ones.

Darguun, Droaam, Valenar and the Carrion Tribes are easy to rationalize gladiator pits. Zilargo is hard, and I imagine it's more of a focused effort to find the most lethal Triumvirate tool. Lhazaar, Mror, all the others - probably national Olympic-style championships.

Of course, there's no need for violence. Lhazaar would have yacht races. Zilargo chess matches (assuming the political jockeying is not ruthless enough for your players). Mror stone carvings, wrestling, or straight-up hammer duels with clerics nearby. And so on.

 

[cmanos]

Wolf, sounds like you are about to create your own homebrew. I wish you luck. It's a lot of fun!

 

[Graf]

Hmmm... I understand a desire to change things, make your own impression. My advice would be to do that on a lower level. Making interesting NPCs, plots and storys your players find interesting, etc.

Instead of making gross (as in large scale) changes I would suggest looking to see if you can get the same kinds of stories with smaller adjustments.

Incidentally it seems like a lot of your changes are related to making the game more like a "standard" DnD world. Have you thought about running Greyhawk?

1. The gods are light on detail, but I think that is reasonable given that they are removed one step compared with gods in other realms. If you want to have active gods you should decide why.

2. 4. Its your game. Those things can be added easily. Which is to say that I think I assumed that anything from the complete books could be in Eberron fairly easily. Personally all the games I've played in where DMs monkeyed around with combat rules went poorly but if your group is keen then go nuts.

3. Given that Eberron is one of the first WotC core settings to encorperate possession rules as well as the major presence of Demons at several stages of history and as major players in the world I think that adding a whole new plane for them is kind of over the top. Demons don't live in the outerplanes in Eberron because (unlike other worlds) they were born on the Material by Kyber. And, at tremendous cost, they were defeated and locked away, but they are still a major force.
There is nothing to say that you could not have had a number of Demons who retreated to a given outer plane and are planting the seeds of their return... but there are lots of demons already present in the setting. (Look at the Demon Wastes, Q'barra sections of the Eberron book, or look up Lords of Dust in Keith Bakers Sharn index.... http://www.bossythecow.com/sharnindex.htm)

5. Espionage is totally Eberron. The first game of our campaign actually featured an underground gladatorial game (six stones) from the Sharn book. It is hard to have in one of the civilized kingdoms, but with the high level of travel and so forth it is definitly possible to have them go someplace for a session or two.

6. The world already has a -lot- in it. I would not add more races myself. Shifters are furries (and they also neatly allow for many different types of classes and abilities in one race, with the shifter bonuses to various stats most classes are quite viable.)

"These are Elves, only Dark and Twisted."

The elves of Eberron are (thank god) broken into several, interesting racial groups. The Undying Court is, if you're willing to think about it, as weird and warped as the Drow was 30 years ago when they showed up.
I have actually had players say to me (like say, last night) "So what's happening next session?"
me "Not sure yet"
Player "Just so long as there are no Drow."
me "Uh... ok. They aren't a big part of the setting you know. And they're fairly different from other worlds."
P "Just don't put any drow in the game, Ok? Anything else is fine."

Lots of people dislike the Drow as they are in Greyhawk, FR, etc. I don't fault WotC for responding to people who were sick of them as they were doing something different and interesting, even if its a departure from the novels we all grew up with as kids (or at least I did).
The core premise of the race is basically entact. They live in a dangerous part of the world where there are riches to be found (in this case Xendrik vs. the underdark), they live in small groups and attack and kill or enslave any who trespass on their lands. The drow were always territorial.
They are probably much less cool from a Players perspective but that suits some people quite well.

On the other hand if you want to put the Drow back under the earth as warped servants of Kyber or modified by Xoriat or excapes from the cataclysm of the giants or exiles from the Elven Kingdoms then that's a very easy change to make.

 

[Plane Sailing]

There is, however, another point about Eberron that bothers me that I can't help but want to change: The Drow.

I'm sorry, but reading all of the descriptions of Eberron's Drow, including the write-up in Races of Eberron, and I can't help but think: "These aren't Drow.. They're dark-skinned Wild Elves." It's not just a matter of spider-worshipping, either. These guys just aren't worthy of the name Drow, 'cause they're not Dark Elves.

Perhaps the Shadow elves are closer to what you think of as drow?

Dragon #330
"Shapers of Shadow: Eberron’s Umbragen" by Keith Baker
Learn about the mysterious shadow elves of Eberron from Keith Baker, the setting’s creator! This reclusive drow sect dwells on the thrilling continent of Xen’drik, manipulating affairs with a special bond to a shadowy realm known as the Umbra. A new prestige class and a variety of feats give you everything you need to insert the Umbragen into your Eberron campaign.

Thumbnails were all I could find of the concept art

 

[Pants]

There is, however, another point about Eberron that bothers me that I can't help but want to change: The Drow.

Personally, I'd cut the drow completely. Not because they are somehow 'less cool,' but because Eberron doesn't have any racial variant races and the drow are exactly that. I'd drop them and replace them with a warped, territorial version of the Khorvaire elves.