Modding in the Planes

[K]

So, the idea was to mod in the DnD Inner and Outer Planes.

Here's the things I'dd think you'd need:
1. Maps that have isolated "no connection" spaces so that the planes can only be reached by travel magic. In those spaces you put in specific sites (Fire sites for Elemental Plane of Fire, etc).
2. Ways of keeping Dominion from bleeding into them.

Now, the first is relatively easy. The second is harder.

Some ideas:

1. Is there a site that removes dominion?
2. How high of a heretic value is possible on a modded unit? I was thinking that there could be units placed in the map that are "Lords of the Planes" with high heretic values and Stealth.

Is any of this possible?