You can put week block under the sand or gravel base to keep plants at
bay. Anything that does grow is easy to pull.
I don't anticipate any serious ongoing maintenance problems after the
pavers are installed. One of my long-time friends who lives in Old Town,
Alexandria, has a house built just after the Civil War that features a
brick patio put in at the same time the house was built. The patio is
brick on sand. It still looks good. Once in a while he gets a little
moss between some of the joints. The moss just adds to the character of
the patio.
Like that little fringe of hair that circles that pumpkin like head of
yours. Adds character indeed.