What would be cool is if there were a way to do a very tall ribbon or planar tweeter like B&G used to make. That make doing a line array with a stack of Neo 10's as midrange units and a single very tall ribbon tweeter next to it a lot less expensive and easier to implement.
I know that this thread is old, but most people don't know that you can buy the Magnepan ribbon from Magnepan -- last I heard, they're $700, but the price may have gone up since then. I'm using it next to a line of 7 Neo 8's. I'm not sure how well it would work with the Neo 10's, since the dispersion of the Neo 10's starts to narrow at about 1 kHz and you'd probably want to cross over the ribbon at 2500 Hz.
You will lose some sensitivity if you do this and have to pad down the Neo 8's -- more than I did when this measurement was taken -- but I prefer the ribbon to the Neos 8's. They're more detailed, airier, with an occasion subtle twang rather than the slightly grainy sound of the Neos. Here they are crossed over at 2500 Hz:

The Neos, on the other hand, sound better at high levels, where the ribbon can start to sound hard. Also, this is without Danny's yarn mod, which improves the dispersion of the Neos, and if you arrange the toe-in so the Neos are a bit off axis you can get rid of the infamous HF hump. And the Neos alone have more precise imaging, consistency, and of course no XO.
I've never compared the ribbon to the Neo 3, though (or the new narrow

. But if nothing else, not having the vertical lobing would be an improvement.
I'd be glad to listen to the Neos alone, but the ribbons have a remarkable realism that the Neos just can't match. I'm toying with the idea of a Neo 10 clone/ribbon combination, with the Neo 8's moved from the sound room to the theater, but that would be a lot of work (new baffles) and money.