I think the more important question is whether (some of the) power pieces should be subject to some anti-trading. In original Dai this was not the case, but that could be one of the reasons it was replaced by Chu in terms of popularity. Tenjiku Shogi also has no anti-trading rules. But I actually played that, and even after trading away the Fire Demons and neutralizing the danger of the jumping generals it remains an enormously tense game, because you can get back a Fire Demon through promotion. Which creates an immediately winning imbalance. The Water Buffalo's themselves are only average pieces (by Tenjuku standards), and are not easily traded. So equiping some less important pieces with decisive promotions might be an alternative to anti-trading for keeping a large game exciting.
I think I will go down the Tenjiku path with Reiwa Dai Shogi, but include moves that reference all the moves found in the historical large variants in some way (including Ko and Taikyoku Shogi), but perhaps in more modest amounts. Here are some of my ideas for the new moves:
Half-Hook Move (RyasRyasW or ByasByasF), a more workable version of the normal Hook Move.
I think I will go down the Tenjiku path with Reiwa Dai Shogi, but include moves that reference all the moves found in the historical large variants in some way (including Ko and Taikyoku Shogi), but perhaps in more modest amounts. Here are some of my ideas for the new moves: