That being said, if you could take a few minutes of your time and include things like the ability to create ESM's and BSA's from the start that would be awesome. Easy import of animations, as well as being able to use them with something besides custom scripts would also be awesome. Thirdly, and access you can give modders to the engine would be rockin! Your "shader packages" decompiled and commented, the ability to turn on anolytic tools like NVidia Performance HUD, full open source- ok maybe that last one will get you attacked in your sleep by lawyers. But the other stuff is surely doable!
And hey players (who like mods): what sort of mods would you like to see that never appeared for previous Bethesda titles?