If you dont like the result that EASY mode rendered, Try use ADVANCED mode.
Lets take a look of 3 different cell mode first
all of them are using same main image, same cell photo collection, and same cell size.
The left is rectangle cell, it is same cell that Easy Photo Mosaic Maker supported.
the middle is hexagon cell, compare to rectangle cells, this one can apply 1.4 times of cell count.
the right one is rectangle cell with division. you can see the eyes and mouth is much clear than the other two.