Well a few games against myself with just the changes to the pieces do
suggest that the Golddragons have an advantage. However, that's before
adding in a further complication of severe restrictions on crossing between
the two middle ranks.
Perhaps I should explain more about thet theme. The setting is either side
of the Bristol Channel, the expanse of water into which the Severn estuary
opens. On one side of this is the well-known territory of Wales, whose flag
features a red dragon that could reasonably be represented by Ryu Shogi's
Copperdragon. On the other is the part of England that in the Dark Ages was
Wessex - comprising the counties of Berkshire, Devon, Dorset, Hampshire,
Somerset, Wight, and Wiltshire. Wessex was one of the many Saxon and
Anglian kingdoms that merged to form the original England. Descriptions of
its flag vary but some accounts credit it with a gold dragon. The suggested
substitution of pieces reflects the predominance of Anglicanism (with
bishops) in England and especially in southern parts such as Wessex, and of
nonconformist churches (Methodist, Baptist, et cetera - without bishops) in
Wales.
As the Bristol Channel forms a more substantial barrier than a river, I
was planning to have most pieces require a Ferry (as per Ferry Xiang Qi) to
cross it. However, any kind of dragon would be presumed able to fly and
therefore not require a ferry. Perhaps a good way to improve the balance
would be to rule that the Rook can also fly, as its English name also means
a kind of bird and its Japanese name - the language of Ryu Shogi's own
name - of Hisha means Flying Chariot.
Now all I need is to think of a name for the variant.