The destruction and foundation visual actors often do not match the sizes of their corresponding structures. E.g. the Persian, Ptolemaic, and Punic wonders all use a 8x8 although respectively 12x12, 9x12, and 6x12 would better match their footprints, obstruction, and visual actor sizes.
It would be nice if someone could create visual actors for more different sizes. Here is a list of nice to have and existing sizes:
art/actors/structures/destruct_stone_* [currently 8]
1x1, 1x2, 1x