Roberto Lavieri thinks that 'this class of game should be excellent in a 7X7 board'. Here is my (never been playtested) suggestion:
bnpwcgh/ddddddd/7/7/7/DDDDDDD/HGCWPNB
where C = Grey Whale Calf, moving straight forward as a wazir, and diagonally backwards as a ferz. Pieces still do not promote in this game, apart from the special killer whale rule. Note that the Grey Whale (and Calf) have the same moves as the Multi General (and Dog) from Tenjiku Shogi.
+---+---+---+---+---+---+---+
7 | H | G | C | W | P | N | B |
+---+---+---+---+---+---+---+
6 | D | D | D | D | D | D | D |
+---+---+---+---+---+---+---+
5 | | | | | | | |
+---+---+---+---+---+---+---+
4 | | | | | | | |
+---+---+---+---+---+---+---+
3 | | | | | | | |
+---+---+---+---+---+---+---+
2 | d | d | d | d | d | d | d |
+---+---+---+---+---+---+---+
1 | b | n | p | w | c | g | h |
+---+---+---+---+---+---+---+
a b c d e f g
bnpwcgh/ddddddd/7/7/7/DDDDDDD/HGCWPNB
where C = Grey Whale Calf, moving straight forward as a wazir, and diagonally backwards as a ferz. Pieces still do not promote in this game, apart from the special killer whale rule. Note that the Grey Whale (and Calf) have the same moves as the Multi General (and Dog) from Tenjiku Shogi.