Hi.
I do WM as well as LotR so I paint and convert both, and love my Menites (Bow, heathens, to the Canon of the True Law)
I can't get a photo u/l right this moment but from personal experience:
They are noticeably taller, and a little 'chunkier' than GW LotR ranges, and the infantry at least would stand apart. You could indeed probably get away with it, but as I said it would be noticeable.
However the choices you listed could work better than most. That Khand hero would be a big fellow, but that's maybe why he's the hero..
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