Nope. I know of no other engine that allows the grade and "easyness" of modding that the gamebroye / creation engine allows and you can't just simply adjust any engine to allow for that. It's in the way the engine works- how mods are loaded, data is stored, etc.
It would surprise me a lot to hear that there are no alternatives to gamebyro that are at least as versatile, or maybe even better, not in everything, but at least in some ways. Particularly today as there are a lot more engines out there chose for your projects compared to the early days of gaming.
Just a quick google search of
top engines for game developers does not really show much of gamebryo. It seems to be that Unreal right now is seeing a lot of attention - mentioned a lot on google, and a few more as seen here -
http://www.moddb.com/engines/rated. I am not saying Gamebryo is inherently bad! - What do I know? That's not what I want to say! It just puzzles me how only so few consider using it, if it seems to be such a good choice.
So I am not saying you're wrong. Popularity is definetly not the best way to measure something here, but it does seem to be kinda strange that no one's really taking much notice from gamebryo, outside of Bethesda, who most probably bought the licence during the stone age of gaming.
It doesn't seem to be a very popular choice today. Not among the big developer companies nor even the independed developers/companies, which have most probably a lot more freedom in which engine they chose for their project. Looking at wikipeda and the current users of the engine, there havn't been a lot of recently developed games that use it.
So what ever quality it might have, it doesn't seem to be a top choice. For what ever reason. And I sure don't want to blame everything on Gamebyro while Bethesda has most probably modified their version of it so much by now, that you could call it their "own" baby by now.
Who knows ... they might just be extremly shitty in their use of said engine, and in that case, it might not really matter WHAT engine they use in the end, as it would always lead to the same results ... :/
By the way, I strongly disagree that you can't adjust engines to be (more) mod friendly, at least the big ones like Unreal, Source etc, becaus at the end of the day, developers who buy some engine, are nothing else but modders as well, if you look at it that way. They have to adjust the engine to their specific project after all. So selling some engine that is extremly difficult to work with, is kinda unfavourable in my opinion.
Again, I am of course no game developer, but I always think one big advantage of the engine is exactly the fact that you can do what ever you want as long you have full access to the source code and all the features the engine offers to you. Some engines might be more difficult to work with, I absolutely agree with that, depending on the structure. But even those can be, and are sometimes, changed.
The fact that Bethesda is always releasing their creation kits is probably contrbuting a lot more here, than the structure of the engine. The community would have to either come up with their own tools or using existing ones, of which both isn't really the best choice. Most companies out there don't release their tools and some make it outright impossible to change the game.
On the other side, something I noticed, it sometimes comes down to how used you are with the engine in question. A lot of people for example find Photoshop, Indesign and/or illustrator confusing and complex, but once you get the hang out of the structure you can develope a very fast work flow. I also always found Blender extremly confusing and difficult to use compared to othe r3D software out there, but there are people which absolutely love it.
Originally Posted by Walpknut 
