I'd add one more. Or two arrays or a composite with 2 arrays.
After all whatever is supposed to take advantage of everything being in one array is going to have some subtle error when the types change out from under it moving from one column to the next. Or you will use Any and it will be horribly slow. Or you will never apply the same operation to all columns at once either by design or as a practical matter to avoid the problems above in which case why are you using 1 array in the first place?
