Here's another idea for the piece arrangement:
(centre square)
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P/GB
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HH/Cm
Kn/Ln
Gs/Ph
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GC/SC
B/DK
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C/S
K
I kept the board the same length, but made a few changes in piece position. I moved everything between the pawn and the copper general back a square. This way, all three front pieces can make the first move and the pawn doesn't get in the way of any of them. The heavenly horse gets in the way of the kirin's second move, but I don't think that'll be much of a problem. The bishop is stuck behind the kirin, but it works as a defense early on.
I also made the RS/B a bishop/dragon king and of course made the changes you suggested (removed the lance and changed the knight to a heavenly horse).