If some are much smaller than others, you can add triangles to each side to make them the size of the larger blocks. You can also add rectangles to each side to make them larger. Square the blocks as you normally would. You can sash the blocks with basically any color that appeals to you or a color that coordinates well with the colors in the blocks. Of course, there is always black, white, beige and grey. Good luck on your project. I, too, just "inherited" 270 four-patch orphan blocks, but at least all of mine measure a scant 4.5". Now to make a couple of charity quilts with them.