Fuel economy sensors have existed since the late 70s so those should be easy to find.
Tire pressure monitoring is likely available in the aftermarket but I haven't looked for it.
As far as how much power goes to each wheel, I'm sure I don't know about that. However if you have locking differentials there's no issue with how much power goes anywhere. There are numerous aftermarket locking differentials for Jeeps, you might want to start at Quadratec, Rock Auto, Morris 4x4 center, or some other store.