I've rearranged and set the urn up on two more pavers. That's as high as I can lift it by myself. Also have to consider the winds, Santa Anas and balmy ocean breezes coming in a gale force from two directions. But that was definitely the right thing to do.
I tried those containers close together at first and from the middle of the street it looked like a big black blob surrounded by a bunch of white rocks. Hence the separating. The total rectangle is 6x10', so I'm going to work with it for awhile, as I can afford to fill in some more.
Thank you for the advice and counsel and sounding board.