Sure, the basis of a mod editor implemented with the game sounds reasonable. But, as I've been prone do to, lemme draw an example with Arcanum.
We all saw the pictures on the back of the box, rite? "Simply click, drag, and place! Presto, brand-spanking-new mod!" Sadly enough, I was hooked and baited by this tempting lure. The ingame editor was anything BUT simple. I recall scratching my head and furrowing my brow when the editor screen showed some grass tile. That was as far as I got.
Now, I'm not saying that the ingame editor was like deciphering Greek. I'm sure that there's a few enlightened folks buzzing away at the mods. But I'm the average-joe-slob teenager gamer. Absolutely no clue in programming at all. Nil. And you can bet the farm on that. And if I had troubles with it, then most of the other average-joe-slob gamers will to.
Sure, there's a bunch of internet manuals that tell you how to make your own mod after sifting through some hundred pages. I'm not willing to risk dislocated eye lenses just to make a mod.
Additionally, you don't see that many Arcanum mods out there, at least as a complete new environment. There's weapon and inventory mods (thx Chris Beddoes) and a few independent game mods (maybe half of those coming from Troika's modpack). Altogether, I'd say there are maybe around twenty or so mods out there, and that's being generous.
