Two words... Suspended track.
I've done a lot of show rooms with high cielings, and what we often did was suspend track to a ladder managable hieght. From there you can aim it anywhere, even up to a certian degree. And it doesn't have to be ugly either, you can do patterns of track, or even fancy monorail in multi-circuit, and have it become a design feature. You can really dress it up, and even hide in or behind stuff. Use pendands on it... I would try to resell the idea - they probhably think the only thing available is Halo, and the many knock-offs.
Like some blown glass pendands like these...
http://www.alfalighting.com/