On balance I like this variant:
Pros:
- Smaller board - I always felt the ExCoCo board a trifle large
- Extra piece - I like the inclusion of the Squirrel
- Increased mobility - The increase from 3 to 4 steps seems about right
- multi-choice castling - excellent, wish I'd thought of it.
Cons:
- really only one - the pawns - the rules for which strike me as overly complex
- well two, but this is only minor, as a Courier variant I would liked to have seen a Courier piece.
and now I feel inspired to apply a few of the positives to ExCoCoChess