I actually just opted for 1x1x5 and a 1x1 round on the top.
From overhead it doesn't look too great, but from the side it's pretty ok.
Thats because you should off set each row after the first one by 1 to the left or right.
If you're feeling creative you could offset one row 1 to the left, and then put the next one
back in the center and then the next one 1 to the right, back to the center, 1 to the left... etc..