I see a lot of assaults and not many mediums in a few of these lists. Also, I'm trying to avoid the unseen to make acquisition easier. so I propose:
King: Atlas
Queen: Stalker
Bishop: Centurion
Knight: Dervish
Rook: Catapult
Pawn: Commando
Obvious OPFOR for this one would be the Clans, which others have covered off on quite nicely already (I'd use a Kitfox as a pawn rather than an elemental personally, just for aesthetics)
I also thought Wolf's Dragoons might be an interesting project, although one or two pieces might be a little harder to get:
King: Archer (alt: Annihilator)
Queen: Warhammer (Alt: Cyclops)
Bishop: Wolfhound
Knight: Hoplite
Rook: Marauder II (Alt: Imp)
Pawn: Flea
The obvious OPFOR for this might be a Succession Wars Kurita force. something like:
King: Hatamoto Chi
Queen: Mauler/Daboku
Bishop: Jenner
Knight: Dragon
Rook: Charger 1A5
Pawn: Panther
Given the nice sculpts of the MW4 lineup currently available, I thought they might make a nice set too:
King: Madcat Mk II
Queen: Vulture Mk[the MW4 looking one]
Bishop: Cougar
Knight: Hellspawn
Rook: Thanatos
Pawn: Osiris
While I was digging for miniatures to make this list, some Clan Invasion and later Liao stuff caught my eye:
King: Yu Huang
Queen: Jinggau
Bishop: Men Shen
Knight: Lao Hu
Rook: Catapult (definitely the C4 resculpt)
Pawn: Raven
Personally I think this last one might be one of the most aesthetically interesting. Note also that keeping things visually consistent yet sufficiently different was a greater consideration for me than game mechanics, although I tried to give a nod in that direction anyway. Feedback welcome as always.