So here we have the same 3 Suiseki placed on different size and different shape Jita. Again, the three placed side-by-side should give you an idea about how the choice of display board can affect the appearance of the Suiseki. In this case, if the Suiseki was being part of a larger display, including other elements like Bonsai and or companion plant, you could make the Suiseki appear more prominent by your choice of Jita.
None of these is incorrect, but rather just different.