Put in an "invisible" helmet...

[SteveMaurer]

These could symbolize tiaras, crowns, circlets, and other non-face obscuring features.

[ShiffDrgnhrt]

there is actually a hak out there for that...  but again, like my hak for the faces with makeup and eye color, it would likely need to be added to the existing layonara Haks in order for it to work

[Alatriel]

Actually, I like that idea too.

[ShiffDrgnhrt]

That might be harder then it sounds, unless someone has files for it to work.  Helmets remove the head in order to function, so you would need a copy of every head with the tiara or crown on it and set them up as head options...  it could be incredibily difficult to implement and I am sure the team wouldn't do that, if that is how it would have to be done.

(has no idea what would be necessary)

[Acacea]

This has been gone over a lot of times - yes, the helmet is not an item worn over the head, but takes the place of the head. You either need, as Shiff mentioned, a duplicate for every single head model, or change the way you use helmets entirely as some have made a project for, which is to wiggle with tails and heads and the like. That's been experimented with and done but it would be a pretty huge PITA for Layo heh.

[darkstorme]

I can't find the hak you were talking about, Shiff.

The only open-faced/invisible helmets I found were ones where people had modded the standard head models to include circlets/helmets/etc, and those only work if you use the same head model.

In general, as Shiff pointed out in his second post, the way the engine deals with someone equipping a helmet is to replace the head of the model.  This is not something that can be readily (if at all) altered; it's part of the game itself.  Attempts to get around it that I've seen include coding "helmet" objects with Unique Item Property: Self attributes, but these were fraught with possible abuses and bugs.

So the short answer would probably be "no, this won't happen".  Not because we wouldn't like it to happen, but because NWN simply isn't designed for it to do so.

Edit: What Acacea said.

[Hellblazer]

I'm currently waiting on some suggestion from script wrecked about how to do this, and will be working on a way to implement all the current heads to the helmet choices... might take a while though. Once submitted to the proper channel for testing and approval that is.
 
 The plan is to limite the current head of the character, to the choices available in the loom.